light a fire under

Idioms

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.

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“It will light a fire under us,” said Aiello, of the Wildlands Network, a conservation nonprofit.

From Los Angeles Times • Feb. 1, 2026

Verona Frankish, chief executive of online estate agent Yopa, said the changes "will certainly light a fire under those buyers currently progressing through the transaction process, or considering a purchase this side of Christmas".

From BBC • Nov. 1, 2024

They’re out there to light a fire under the base,” he said.

From Washington Times • Sep. 30, 2023

“It can’t but light a fire under my colleagues to explore policy solutions.”

From Seattle Times • Feb. 23, 2023

“Do you think the senator will be able to light a fire under them and get people in here to save us?”

From "Time Bomb" by Joelle Charbonneau

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023