Nip in the bud comes from horticulture, where trimming a bud from a plant prevents the bud from becoming a flower or fruit. Used metaphorically, the phrase usually means to stop a potential problem before it develops. For example, you might nip an argument in the bud by coming to a compromise immediately, or you might nip an illness in the bud by taking medicine as soon as you feel symptoms.
Some plants thrive when buds are selectively nipped—even when the nipped buds are not especially harmful—so a slightly different metaphorical meaning of nip in the bud would be to end something early for the sake of a greater good. But the phrase is usually used in the first sense.
Nip in the butt is suprisingly common. On the web, it appears about once for every 18 instances of nip in the bud. Nip in the butt can make sense if we use our imagination, but it’s usually just a misspelling of nip in the bud.
And now Nadal shows signs, for the third consecutive set, of nipping a Djokovic would-be comeback in the bud. [Wall Street Journal]
The European debt crisis is nipping our incipient recovery in the bud. [Time]
Afghanistan’s National Directorate of Security is trying to nip terrorism in the bud by sending would-be suicide bombers to a kind of spiritual rehab. [New York Daily News]
[I]t might have been wise for Sky to have considered nipping unrest in the bud by offering consumers significantly better value for money. [Stuff.co.nz]
If the coach is smart, he or she will tuck this information away and be on the lookout to nip any bad behavior in the bud before it escalates. [Chicago Tribune]