Sentence:  <WSD>COOPING</WSD>. The term "cooping" refers to police officers sleeping on duty. ... One critic of two-man squad cars suggests that this is a recipe for <WSD>cooping</WSD>, since one officer can drive while the other sleeps. 
Meaning of the word marked with <WSD> tags:  Of a police officer: to sleep or relax while on duty. (from 1960s.)