suboperculum /sub-o-pûrˈkū-ləm or -ō-/

(in fishes) a bone below and partly behind the gill cover

suboperˈcular adjective

• at one's elbow
• at one's finger-ends
• at one's finger's-ends
• at one's fingertips
• at one's leisure
• at one's wit's end
• at one time
• atonic
• atonicities
• atonicity
• atonies
• atoning
• atoningly
• atony
• atop
• atopic
• atopies
• a top noise
• atopy
• atorvastatin
• atorvastatins
• a touch of the sun
• a tough nut to crack
• at outs
• ATP