cognoscente /ko-nyō-shenˈtā/

1. A person professing an expert knowledge, esp of works of art, music, literature, etc
2. A connoisseur

• on every hand
• one-way
• one way and another
• one-way glass
• one-way mirror
• one way or the other
• one with another
• one-woman
• one-worlder
• one-worlders
• one-worldism
• oneyer
• oneyers
• oneyre
• oneyres
• onfall
• onfalls
• on file
• on fire
• on firm ground
• onflow
• onflows
• on foot
• on-going
• ongoing