An unforeseen event that disrupts the normal course of things; an inopportune occurrence; a mischance or mishap.

From the French contre-, meaning against, and temps, meaning time.

Pronounced KON-truh-tan or kawn-truh-TAN. (in either case, the last syllable should be pronounced with the nasal passage open, giving it that French twang). The plural is spelled exactly the same way, but pronounced with a 'z' sound on the end; KON-truh-tanz.