Synonyms: undermanned, understaffed, short-handed, short-staffed
Definition: inadequate in number of workers or assistants etc.
Usage: they're rather short-handed at the moment; overcrowded and understaffed hospitals
Similar words: unequal, inadequate
Definition: lacking the requisite qualities or resources to meet a task
Usage: inadequate training; the staff was inadequate; she was unequal to the task