- one-track mind,
- one-trick pony,
- one-way mirror,
- one-way ticket,
Origin of one-upmanship
Examples from the Web for one-upmanship
Too often we focus on one-upmanship and demonization of those whose points of view are different from our own.Roland Martin Made Mistakes in Tweets Deemed Antigay but Is No Homophobe|Phill Wilson|February 16, 2012|DAILY BEAST
The gesture strikes me as hostile, and vaguely chauvinistic; how pathetic, I think, that his impulse is one-upmanship.
A call girl's idea of one-upmanship—which is far more beneficial to the men she sees—is being more discreet than the next girl.