Manpower is all the workers you have — or can get — for a job: enough people to run a factory, staff a hospital, or fill an army. Offices and newspapers still say “a manpower shortage” when they mean “not enough hands.” It is a slightly official, older-sounding word. Though actually, it has long meant people of any gender, not only men; even so, many workplaces now prefer workforce or staff, because manpower can sound as if only men count. It is not “a man’s physical strength.” You also see it in company names, where it just means “workers we can send.”