-təˌdərm noun
( -s )
Etymology: International Scientific Vocabulary ect- + -derm
1. : the outer cellular membrane of a medusa or other diploblastic animal
2. : the outermost of the three primary germ layers of an embryo : the source of neural tissue and sense organs, of the outer layer of the skin, and of minor adult structures : epiblast ; also : any tissue wherever located derived from this germ layer — compare epidermis
• ec·to·der·mal | ̷ ̷ ̷ ̷|dərməl or ec·to·der·mic -mik adjective