The Collaborative International Dictionary
Phylactocarp
Phylactocarp \Phy*lac"to*carp\, n. [Gr. ? to guard + ? fruit.] (Zo["o]l.) A branch of a plumularian hydroid specially modified in structure for the protection of the gonothec[ae].
Wiktionary
phylactocarp
n. (context zoology English) A branch of a plumularian hydroid specially modified in structure for the protection of the gonothecae.