light a fire under


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Related to light a fire under: alight

light a fire under (someone or something)

To motivate someone or something to take action. The deadline really lit a fire under us—we never would have gotten all that work done otherwise. Something must have lit a fire under Jenna—she has really started taking her schoolwork seriously.
See also: fire, light
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

light a fire under

Also, build a fire under. Urge or goad to action, as in If we don't light a fire under that committee, they'll never do any work. This hyperbolic colloquialism uses light in the sense of "ignite," a usage dating from the mid-1100s.
See also: fire, light
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

light a fire under

To urge or move to action.
See also: fire, light
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
See also: