IPA: /ˌʌndərˈstæft/
KK: /ʌndərˈstæft/
Having too few workers to handle the tasks or responsibilities effectively.
The restaurant was understaffed, leading to long wait times for customers.
Understaffed → It is formed from "under-" (meaning below or insufficient) and "staff" (from Old English *stæf*, meaning a group of people or personnel). The word "understaffed" means having insufficient staff or personnel to meet needs or demands.
Think of having 'insufficient' ('under-') 'staff' or personnel — that's why understaffed means not having enough people.