Medical Definition of Gnathobdellida
: an order or other taxon of leeches comprising those lacking a proboscis and having 2-toothed or 3-toothed chitinous jaws (as the medicinal leech and the land leeches)
Seen and Heard
What made you want to look up Gnathobdellida? Please tell us where you read or heard it (including the quote, if possible).