Definition from Wiktionary, the free dictionary
roshambo (plural roshambos)
- (games) the game of rock paper scissors
- (as three words, ro sham bo) the syllables called out by players of rock paper scissors to synchronize their timing.
- To play a game of roshambo in order to decide a point of contention.
- I'll roshambo you for it.
- toss (as in 'toss a coin')