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Unified Medical Language System® (UMLS®)

Current Semantic Types



    Physical Object
        Anatomical Structure
            Embryonic Structure
            Anatomical Abnormality
                Congenital Abnormality
                Acquired Abnormality
            Fully Formed Anatomical Structure
                Body Part, Organ, or Organ Component
                Cell Component
                Gene or Genome
        Manufactured Object
            Medical Device
                Drug Delivery Device
            Research Device
            Clinical Drug
                Chemical Viewed Functionally
                    Pharmacologic Substance
                    Biomedical or Dental Material
                    Biologically Active Substance
                        Immunologic Factor
                    Indicator, Reagent, or Diagnostic Aid
                    Hazardous or Poisonous Substance

    [Physical Object] (continued)
        [Substance] (continued)
            [Chemical] (continued)
                Chemical Viewed Structurally
                    Organic Chemical
                        Nucleic Acid, Nucleoside, or Nucleotide
                        Amino Acid, Peptide, or Protein
                    Inorganic Chemical
                    Element, Ion, or Isotope
            Body Substance
    Conceptual Entity
        Idea or Concept
            Temporal Concept
            Qualitative Concept
            Quantitative Concept
            Functional Concept
                Body System
            Spatial Concept
                Body Space or Junction
                Body Location or Region
                Molecular Sequence
                    Nucleotide Sequence
                    Amino Acid Sequence
                    Carbohydrate Sequence
                Geographic Area
            Laboratory or Test Result
            Sign or Symptom
        Organism Attribute
            Clinical Attribute
        Intellectual Product
            Regulation or Law
        Occupation or Discipline
            Biomedical Occupation or Discipline
            Health Care Related Organization
            Professional Society
            Self-help or Relief Organization
        Group Attribute
            Professional or Occupational Group
            Population Group
            Family Group
            Age Group
            Patient or Disabled Group




            Social Behavior
            Individual Behavior
        Daily or Recreational Activity
        Occupational Activity
            Health Care Activity
                Laboratory Procedure
                Diagnostic Procedure
                Therapeutic or Preventive Procedure
            Research Activity
                Molecular Biology Research Technique
            Governmental or Regulatory Activity
            Educational Activity
        Machine Activity
    Phenomenon or Process
        Human-caused Phenomenon or Process
            Environmental Effect of Humans

    [Phenomenon or Process] (continued)
        Natural Phenomenon or Process
            Biologic Function
                Physiologic Function
                    Organism Function
                        Mental Process
                    Organ or Tissue Function
                    Cell Function
                    Molecular Function
                        Genetic Function
                Pathologic Function
                    Disease or Syndrome
                        Mental or Behavioral Dysfunction
                        Neoplastic Process
                    Cell or Molecular Dysfunction
                    Experimental Model of Disease
        Injury or Poisoning

Last Reviewed: May 10, 2016