1. To hire the necessary members of staff. A lot of the retail shops around here staff up with temporary workers for the holiday rush.
2. To fill a business with employees or staff members. In this usage, a noun or pronoun can be used between "staff" and "up." The new restaurant is supposed to open in a week, but owners still haven't staffed it up completely.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.