You should probably postpone dinner if your date's cold is contagious — that means it's easily spread and likely to get you sick.
Contagious actually evolved from contagio, the Latin phrase for “contact." Those smart ancient Romans — they figured out that the sick and contagious can pass on their plague to those they touch or get close to. So the word contagious usually sends people running. But let’s not forget that a smile or good deed can be just as infectious as a cough!