swing shift

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The work shift between the day and the night shifts, usually 4 PM to midnight.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun US A work shift between a day shift and a night shift, such as from 4PM to midnight, and the group of workers scheduled to work such a shift at a facility.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the work shift during the evening (as 4 p.m. to midnight)