ONE-UP Meaning of ONE-UP in English ¦ ̷ ̷ ˈ ̷ ̷ transitive verb( one-upped ; one-upped ; one-upping ; one-ups )Etymology: back-formation from one-upmanship : to practice one-upmanship on Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012