cys·to·carp \ˈsistəˌkärp, -stōˌ-\noun (-s) Etymology: International Scientific Vocabulary cyst- + -carp : the fruiting structure produced in the red algae after fertilization; especially: such a structure having a special protective envelope (as in Polysiphonia) • cys·to·car·pic\| ̷ ̷ ̷ ̷| ̷ ̷pik\adjective