Longman Dictionary of Contemporary English
lunch hour
noun
EXAMPLES FROM CORPUS
▪ During her lunch hour she shopped, deliberately avoiding the part of town in which Giles's office was situated.
▪ Friday: the long lunch hour at the York.
▪ He had roamed Queenstown during his lunch hour at the beginning of the week before he could find a roaster for sale.
▪ I went to over the lunch hour.
▪ Nearly everyone, however, even on casual Friday, is drinking soda or tea during the lunch hour.
▪ Walk for fifteen minutes each lunch hour.
Wikipedia
Lunch Hour
Lunch Hour is a 1961 film based on a one-act play by John Mortimer. It is about a man and a woman who attempt to have an affair during their lunch hour, but are continually interrupted. Shirley Ann Field described it as perhaps "the most enjoyable film I'd ever done" because the cast and crew all worked so closely together.