sharpenersharp‧en‧er /ˈʃɑːpənə, ˈʃɑːpnə $ ˈʃɑːrpənər, ˈʃɑːrpnər/ noun [countable] Word Family: noun: sharpener, sharpness, sharp; adverb: sharp, sharply, sharpish; verb: sharpen; adjective: sharpa tool or machine for sharpening pencils, knives etc