part_of part of part of has boundary has 2D boundary capable of capable of existence starts during or after material entity material entity biological_process organ element EMAPA:35949 SCTID:272625005 CARO:0020004 FMA:67498 WBbt:0003760 CARO v1 does not include a generic 'organ' class, only simple and compound organ. CARO v2 may include organ, see https://github.com/obophenotype/caro/issues/4 uberon body organ UBERON:0000062 anatomical unit MA:0003001 NCIT:C13018 BIRNLEX:4 OpenCyc:Mx4rwP3iWpwpEbGdrcN5Y29ycA Organs are commonly observed as visibly distinct structures, but may also exist as loosely associated clusters of cells that work together to perform a specific function or functions. EFO:0000634 UMLS:C0178784 Anatomical structure that performs a specific function or group of functions [WP]. Wikipedia:Organ_(anatomy) OpenCyc:Mx4rv5XMb5wpEbGdrcN5Y29ycA ENVO:01000162 organogenesis stage anatomical system anatomical surface multicellular anatomical structure