- (intr, preposition) to have influence to the disadvantage ofyour bad timekeeping will count against you
Idioms and Phrases with count against
Be disadvantageous to, as in His earnings this year will count against his Social Security benefits. This idiom uses count in the sense of “make a reckoning,” in this case negative. [Early 1900s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.