{v.}, {informal} Always keeping ahead of others; trying to keep an advantage. * /No matter what I do, I find that Jim has already done it better. He's an expert at one-upmanship./ * /Jack took the news to the principal while we were still talking about it. He's very quick to practice one-upmanship./ Compare: ONE UP. (The word one-upmanship was made up by a British humorist, Stephen Potter, on the pattern of such words as sportsmanship and workmanship.)
ONE-UPMANSHIP
Meaning of ONE-UPMANSHIP in English
Dictionary of English idioms . Словарь английских идиом. 2012