understaffing

/AH1 N D ER0 S T AE0 F IH0 NG/
verb
  1. 1

    To furnish with too few staff; to staff inadequately.

noun
  1. 1

    The situation of having insufficient members of staff.

Source: https://en.wiktionary.org/wiki/understaff, https://en.wiktionary.org/wiki/understaffing