A repairman is someone whose job is to fix things — an air-conditioner, a washing machine, a car, depending on the kind of repairman. The word is one piece, not ‘repair man.’ It is still common in American speech and in older stories and textbooks, but it is a little old-fashioned in a gentle way, because it has man in it. Plenty of people who do this work are not men. Younger speakers and companies more often say technician, engineer, or repair person. You still need the word, because you will meet it; you do not have to use it if another word fits the person better.

修理工；維修師傅（口語常直接說師傅）