NCI Metathesaurus (NCIm) (download) is a wide-ranging biomedical terminology database that covers most terminologies used by NCI for clinical care, translational and basic research, and public information and administrative activities.
The database contains 2.000,000 concepts mapped to 4.000,000 terms with 22,000,000 relationshipscontains 3,653,463 concepts mapped to 8,015,800 terms with 24,060,058 relationships with 106 sources. NCIm contains most public domain vocabularies from the National Library of Medicine's UMLS Metathesaurus, as well as many other biomedical vocabularies. Some propriety vocabularies are included, and have restrictions on their use.
NCIm is registered in the HL7 OID Registry
Comments and suggestions may be emailed to the NCIm team at NCIMetathesaurus@mail.nih.gov.