| Relation Name/Additional Label | Expanded Form | Count |
| PAR/inverse_isa | has parent relationship in a Metathesaurus source vocabulary /Inverse is a | 104341 |
| CHD/isa | has child relationship in a Metathesaurus source vocabulary /Is a | 104341 |
| RO/has_regional_part | has relationship other than synonymous, narrower, or broader/Has regional part | 27672 |
| RO/regional_part_of | has relationship other than synonymous, narrower, or broader/Regional part of | 27672 |
| RO/has_constitutional_part | has relationship other than synonymous, narrower, or broader/Has constitutional part | 21492 |
| RO/constitutional_part_of | has relationship other than synonymous, narrower, or broader/Constitutional part of | 21492 |
| RO/branch_of | has relationship other than synonymous, narrower, or broader/Branch of | 7032 |
| RO/has_branch | has relationship other than synonymous, narrower, or broader/Has branch | 7032 |
| RO/has_member | has relationship other than synonymous, narrower, or broader/Has member | 4542 |
| RO/member_of | has relationship other than synonymous, narrower, or broader/Member of | 4542 |
| RO/related_part | has relationship other than synonymous, narrower, or broader/related part | 3574 |
| RO/continuous_with | has relationship other than synonymous, narrower, or broader/Continuous with | 2512 |
| RO/has_nerve_supply | has relationship other than synonymous, narrower, or broader/Has nerve supply | 2133 |
| RO/nerve_supply_of | has relationship other than synonymous, narrower, or broader/Nerve supply of | 2133 |
| RO/continuous_distally_with | has relationship other than synonymous, narrower, or broader/continuous distally with | 1948 |
| RO/continuous_proximally_with | has relationship other than synonymous, narrower, or broader/continuous proximally with | 1948 |
| RO/has_tributary | has relationship other than synonymous, narrower, or broader/Has tributary | 1138 |
| RO/tributary_of | has relationship other than synonymous, narrower, or broader/Tributary of | 1138 |
| RO/bounds | has relationship other than synonymous, narrower, or broader/Bounds | 1080 |
| RO/bounded_by | has relationship other than synonymous, narrower, or broader/Bounded by | 1080 |
| RO/contained_in | has relationship other than synonymous, narrower, or broader/Contained in | 893 |
| RO/contains | has relationship other than synonymous, narrower, or broader/Contains | 893 |
| RO/afferent_to | has relationship other than synonymous, narrower, or broader/Afferent to | 823 |
| RO/efferent_to | has relationship other than synonymous, narrower, or broader/Efferent to | 823 |
| RO/receives_input_from | has relationship other than synonymous, narrower, or broader/Receives input from | 811 |
| RO/sends_output_to | has relationship other than synonymous, narrower, or broader/Sends output to | 811 |
| RO/lymphatic_drainage_of | has relationship other than synonymous, narrower, or broader/Lymphatic drainage of | 764 |
| RO/has_lymphatic_drainage | has relationship other than synonymous, narrower, or broader/Has lymphatic drainage | 764 |
| SY/has_expanded_form | source asserted synonymy./Has expanded form | 732 |
| SY/expanded_form_of | source asserted synonymy./Expanded form of | 732 |
| RO/has_segmental_supply | has relationship other than synonymous, narrower, or broader/Has segmental supply | 705 |
| RO/segmental_supply_of | has relationship other than synonymous, narrower, or broader/Segmental supply of | 705 |
| RO/articulates_with | has relationship other than synonymous, narrower, or broader/Articulates with | 692 |
| RO/arterial_supply_of | has relationship other than synonymous, narrower, or broader/Arterial supply of | 632 |
| RO/has_arterial_supply | has relationship other than synonymous, narrower, or broader/Has arterial supply | 632 |
| RO/posterior_to | has relationship other than synonymous, narrower, or broader/posterior to | 545 |
| RO/anterior_to | has relationship other than synonymous, narrower, or broader/anterior to | 545 |
| RO/attaches_to | has relationship other than synonymous, narrower, or broader/Attaches to | 500 |
| RO/receives_attachment_from | has relationship other than synonymous, narrower, or broader/receives attachment from | 500 |
| RO/direct_right_of | has relationship other than synonymous, narrower, or broader/direct right of | 487 |
| RO/direct_left_of | has relationship other than synonymous, narrower, or broader/direct left of | 487 |
| RO/superior_to | has relationship other than synonymous, narrower, or broader/superior to | 469 |
| RO/inferior_to | has relationship other than synonymous, narrower, or broader/inferior to | 469 |
| RO/has_origin | has relationship other than synonymous, narrower, or broader/Has origin | 277 |
| RO/origin_of | has relationship other than synonymous, narrower, or broader/Origin of | 277 |
| RO/derives | has relationship other than synonymous, narrower, or broader/derives | 274 |
| RO/derives_from | has relationship other than synonymous, narrower, or broader/derives from | 274 |
| RO/receives_drainage_from | has relationship other than synonymous, narrower, or broader/receives drainage from | 254 |
| RO/drains_into | has relationship other than synonymous, narrower, or broader/drains into | 254 |
| RO/related_object | has relationship other than synonymous, narrower, or broader/related object | 252 |
| RO/has_insertion | has relationship other than synonymous, narrower, or broader/has insertion | 213 |
| RO/insertion_of | has relationship other than synonymous, narrower, or broader/insertion of | 213 |
| RO/medial_to | has relationship other than synonymous, narrower, or broader/medial to | 207 |
| RO/lateral_to | has relationship other than synonymous, narrower, or broader/lateral to | 207 |
| RO/developmental_stage_of | has relationship other than synonymous, narrower, or broader/developmental stage of | 193 |
| RO/has_developmental_stage | has relationship other than synonymous, narrower, or broader/has developmental stage | 193 |
| RO/proximal_to | has relationship other than synonymous, narrower, or broader/proximal to | 182 |
| RO/distal_to | has relationship other than synonymous, narrower, or broader/distal to | 182 |
| RO/surrounds | has relationship other than synonymous, narrower, or broader/Surrounds | 140 |
| RO/connected_to | has relationship other than synonymous, narrower, or broader/connected to | 140 |
| RO/surrounded_by | has relationship other than synonymous, narrower, or broader/Surrounded by | 140 |
| RO/has_venous_drainage | has relationship other than synonymous, narrower, or broader/Has venous drainage | 132 |
| RO/venous_drainage_of | has relationship other than synonymous, narrower, or broader/Venous drainage of | 132 |
| RO/receives_projection | has relationship other than synonymous, narrower, or broader/receives projection | 117 |
| RO/projects_to | has relationship other than synonymous, narrower, or broader/projects to | 117 |
| RO/projects_from | has relationship other than synonymous, narrower, or broader/projects from | 112 |
| RO/has_projection | has relationship other than synonymous, narrower, or broader/has projection | 112 |
| RO/has_primary_segmental_supply | has relationship other than synonymous, narrower, or broader/Has primary segmental supply | 81 |
| RO/primary_segmental_supply_of | has relationship other than synonymous, narrower, or broader/Primary segmental supply of | 81 |
| RO/has_secondary_segmental_supply | has relationship other than synonymous, narrower, or broader/Has secondary segmental supply | 80 |
| RO/secondary_segmental_supply_of | has relationship other than synonymous, narrower, or broader/Secondary segmental supply of | 80 |
| RO/matures_from | has relationship other than synonymous, narrower, or broader/matures from | 76 |
| RO/matures_into | has relationship other than synonymous, narrower, or broader/matures into | 76 |
| RO/homonym_of | has relationship other than synonymous, narrower, or broader/Homonym of | 73 |
| RO/homonym_for | has relationship other than synonymous, narrower, or broader/Homonym for | 73 |
| RO/anteromedial_to | has relationship other than synonymous, narrower, or broader/anteromedial to | 53 |
| RO/posterolateral_to | has relationship other than synonymous, narrower, or broader/posterolateral to | 53 |
| RO/transforms_from | has relationship other than synonymous, narrower, or broader/transforms from | 50 |
| RO/transforms_into | has relationship other than synonymous, narrower, or broader/transforms into | 50 |
| RO/corresponds_to | has relationship other than synonymous, narrower, or broader/corresponds to | 46 |
| RO/continuation_branch_of | has relationship other than synonymous, narrower, or broader/Continuation branch of | 43 |
| RO/has_continuation_branch | has relationship other than synonymous, narrower, or broader/Has continuation branch | 43 |
| RO/anteroinferior_to | has relationship other than synonymous, narrower, or broader/anteroinferior to | 41 |
| RO/posterosuperior_to | has relationship other than synonymous, narrower, or broader/posterosuperior to | 41 |
| RO/posteromedial_to | has relationship other than synonymous, narrower, or broader/posteromedial to | 39 |
| RO/anterolateral_to | has relationship other than synonymous, narrower, or broader/anterolateral to | 39 |
| RO/posteroinferior_to | has relationship other than synonymous, narrower, or broader/posteroinferior to | 35 |
| RO/anterosuperior_to | has relationship other than synonymous, narrower, or broader/anterosuperior to | 35 |
| RO/fuses_with | has relationship other than synonymous, narrower, or broader/fuses with | 26 |
| RO/part_of | has relationship other than synonymous, narrower, or broader/Part of | 23 |
| RO/has_part | has relationship other than synonymous, narrower, or broader/Has part | 23 |
| RO/adjacent_to | has relationship other than synonymous, narrower, or broader/Adjacent to | 22 |
| RO/develops_into | has relationship other than synonymous, narrower, or broader/develops into | 21 |
| RO/develops_from | has relationship other than synonymous, narrower, or broader/Develops from | 21 |
| RO/inferomedial_to | has relationship other than synonymous, narrower, or broader/inferomedial to | 20 |
| RO/inferolateral_to | has relationship other than synonymous, narrower, or broader/inferolateral to | 20 |
| RO/superolateral_to | has relationship other than synonymous, narrower, or broader/superolateral to | 20 |
| RO/superomedial_to | has relationship other than synonymous, narrower, or broader/superomedial to | 20 |
| RO/has_related_developmental_entity | has relationship other than synonymous, narrower, or broader/has related developmental entity | 15 |
| RO/formed_by | has relationship other than synonymous, narrower, or broader/formed by | 15 |
| RO/forms | has relationship other than synonymous, narrower, or broader/forms | 15 |
| RO/related_developmental_entity_of | has relationship other than synonymous, narrower, or broader/related developmental entity of | 15 |
| RO/has_development_type | has relationship other than synonymous, narrower, or broader/has development type | 13 |
| RO/development_type_of | has relationship other than synonymous, narrower, or broader/development type of | 13 |
| RO/has_fusion | has relationship other than synonymous, narrower, or broader/has fusion | 7 |
| RO/has_adherent | has relationship other than synonymous, narrower, or broader/Has adherent | 7 |
| RO/adheres_to | has relationship other than synonymous, narrower, or broader/Adheres to | 7 |
| RO/fusion_of | has relationship other than synonymous, narrower, or broader/fusion of | 7 |
| RO/merges_with | has relationship other than synonymous, narrower, or broader/merges with | 6 |
| RO/left_lateral_to | has relationship other than synonymous, narrower, or broader/left lateral to | 5 |
| RO/right_lateral_to | has relationship other than synonymous, narrower, or broader/right lateral to | 5 |
| RO/right_medial_to | has relationship other than synonymous, narrower, or broader/right medial to | 5 |
| RO/left_medial_to | has relationship other than synonymous, narrower, or broader/left medial to | 5 |
| RO/inherent_3d_shape_of | has relationship other than synonymous, narrower, or broader/Inherent 3-D shape of | 4 |
| RO/has_connection_type | has relationship other than synonymous, narrower, or broader/has connection type | 4 |
| RO/connection_type_of | has relationship other than synonymous, narrower, or broader/connection type of | 4 |
| RO/has_inherent_3d_shape | has relationship other than synonymous, narrower, or broader/Has inherent 3-D shape | 4 |
| RO/has_full_grown_phenotype | has relationship other than synonymous, narrower, or broader/has full grown phenotype | 3 |
| RO/has_observed_anatomical_entity | has relationship other than synonymous, narrower, or broader/has observed anatomical entity | 3 |
| RO/anatomical_entity_observed_in | has relationship other than synonymous, narrower, or broader/anatomical entity observed in | 3 |
| RO/full_grown_phenotype_of | has relationship other than synonymous, narrower, or broader/full grown phenotype of | 3 |
| RO/has_direct_cell_shape | has relationship other than synonymous, narrower, or broader/has direct cell shape | 2 |
| RO/has_location | has relationship other than synonymous, narrower, or broader/Has location | 2 |
| RO/direct_cell_shape_of | has relationship other than synonymous, narrower, or broader/direct cell shape of | 2 |
| RO/location_of | has relationship other than synonymous, narrower, or broader/Location of | 2 |
| RO/has_segmental_composition | has relationship other than synonymous, narrower, or broader/Has segmental composition | 2 |
| RO/segmental_composition_of | has relationship other than synonymous, narrower, or broader/Segmental composition of | 2 |
| RO/external_to | has relationship other than synonymous, narrower, or broader/external to | 1 |
| RO/has_germ_origin | has relationship other than synonymous, narrower, or broader/Has germ origin | 1 |
| RO/internal_to | has relationship other than synonymous, narrower, or broader/internal to | 1 |
| RO/germ_origin_of | has relationship other than synonymous, narrower, or broader/Germ origin of | 1 |
