hands vs manpower

hands and manpower both are nouns.

Word	Noun	Adjective	Verb	Adverb
hands	Yes	No	No	No
manpower	Yes	No	No	No

As nouns, hands and manpower are synonyms defined as:

Other synonyms of hands include men, work force, workforce.

hands (noun)	manpower (noun)
(with `in') guardianship over; in divorce cases it is the right to house and care for and discipline a child	the force of workers available
the force of workers available