n. [ Thienyl + ketone. ] (Chem.) A ketone derivative of thiophene obtained as a white crystalline substance, (C4H3S)2.CO, by the action of aluminum chloride and carbonyl chloride on thiophene. [ 1913 Webster ]
n. [ Thiophene + -yl. ] (Chem.) The hypothetical radical C4H3S., regarded as the essential residue of thiophene and certain of its derivatives. [ 1913 Webster ]