Question to good English grammar experts-is it true that the words in the list refer to both a man or a woman:?

A fireman,a stewardess,a waiter,a policeman,a fisherman,a chairman. They are from one task on jobs for men and women. But there is no problem to find in the dictionary the words like steward, waitress. Can we call a man- a stewardess or a woman - a waiter or policeman?