Result from Foreign Dictionaries (2 entries found)
From The Collaborative International Dictionary of English v.0.48 [gcide]:
one-upmanship \one-upmanship\ n.
The attitude or practice of trying to keep one step ahead of
a friend or competitor; vigorous competitiveness.
[WordNet 1.5 +PJC]
From WordNet (r) 3.0 (2006) [wn]:
one-upmanship
n 1: the practice of keeping one jump ahead of a friend or
competitor