burning the midnight oil

working very long hours, often into the night What doctors do know is that burning the midnight oil is bad for your health.

Etymology: from the use of oil to provide light before the invention of electricity

Name	Pronounced	Usage
Yosyp	-	Ukrainian
Albert	AL-bərt (English), al-BER (French), AHL-bert (German, Polish), AHL-bərt (Dutch)	English, French, Catalan, German, Polish, Russian, Dutch, Swedish, Norwegian, Danish, Icelandic, Rom
Austins	['ɔstinz]
Cyriaca	-	Late Roman
Mercy	['mə:si]
Bonner	['bɔnə]