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have a case on

Idioms  

  1. Also, have a crush on. Be infatuated with someone, as in He's had a case on her for years, or Teenage girls often have a crush on this teacher. The first slangy term dates from the mid-1800s; the second, a colloquialism, dates from the late 1800s.

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

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