cy·clos·to·mate \(ˈ)sīˈklästəmə̇t\adjective alsocy·clo·stom·a·tous\| ̷ ̷ ̷ ̷ at cyclo-+|stäməd.əs, -tōm-\ Etymology: in sense 1, from cycl- + -stomate or -stomatous; in sense 2, cyclostomate from New Latin Cyclostomata; cyclostomatous from New Latin Cyclostomata + English -ous 1.: having a circular mouth 2.: of or relating to the Cyclostomata or Cyclostomi