multi-tissue structure Anatomical structure that has as its parts two or more portions of tissue of at least two different types and which, through specific morphogenetic processes, forms a single distinct structural unit demarcated by bona fide boundaries from other distinct structural units of different types. FBbt:00007010 fly_anatomy.ontology UBERON:0000481 CARO:0000055 cell cluster organ compound cell cluster organ multicellular structure