fire under

*fire under someone

Fig. something that makes someone start doing something. (*Typically: build ~; light ~; start ~.) The teacher built a fire under the students, and they really started working. You had better light a fire under your staff. Either that or we will lay off some of them.
See also: fire
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in classic literature ?
It seems that each green warrior has certain objective points for his fire under relatively identical circumstances of warfare.
Baldia factory was set on fire under a plan, says IO
Fire fighters after the struggle of three hours were able to bring the fire under control after that they started the cooling process with one fire tender to avoid the eruption of fire once again.