rhabdocoele
noun
rhab·do·coele ˈrab-də-ˌsēl 
: a turbellarian worm (order Rhabdocoela) with an unbranched intestine
Word History
Etymology
borrowed from New Latin Rhabdocoela, order name, from rhabdo- rhabdo- + -coela -coele
First Known Use
1883, in the meaning defined above