trem·a·tode 
(tr
ĕm
ə-t
ōd
′)
n. Any of numerous flatworms of the class Trematoda, including both external and internal parasites of animal hosts, that have a thick outer cuticle and one or more suckers or hooks for attaching to host tissue.
[From New Latin Trēmatōda, class name, from Greek trēmatōdēs, having holes, from trēma, trēmat-, perforation; see terə-1 in the Appendix of Indo-European roots.]
trema·tode′ adj.