Part of speech: Adjective (satellite)
inadequate in number of workers or assistants etc.
Example: they're rather short-handed at the moment; overcrowded and understaffed hospitals
Understaffed, Short-staffed, Undermanned, Short-handed
under – A related word in the same word family.
staffed – A related word in the same word family.
Children naturally create grammatical rules, showing language is hardwired in human brains.