midnight oil

see burn the midnight oil.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.

Examples from the Web for midnight oil

  • There are two varieties of college students—the midnight-oil and the natural-gas kind; and Petey was a whole gas well in himself.

    At Good Old Siwash|George Fitch
  • The days were all too short, and soon the midnight-oil began to burn.

    Poppy|Cynthia Stockley