look a gift horse in the mouth

Idioms  

1. Be critical or suspicious of something received at no cost. For example, Dad's old car is full of dents, but we shouldn't look a gift horse in the mouth. This term, generally expressed as a cautionary proverb (Don't look a gift horse in the mouth), has been traced to the writings of the 4th-century cleric, St. Jerome, and has appeared in English since about 1500. It alludes to determining the age of a horse by looking at its teeth.

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Example Sentences

Customers won’t look a gift horse in the mouth, but it smacks of the expensive land grab that worries some U.S. tech investors.

From The Wall Street Journal • Feb. 17, 2026

Never look a gift horse in the mouth, goes the old saying.

From Barron's • Dec. 19, 2025

Trumble pointed to the famous expression "don't look a gift horse in the mouth" as proof that people have always suspected a connection between health and examining an animal's teeth.

From Salon • Mar. 26, 2024

In response to these suggestions, some might say it’s rude to look a gift horse in the mouth.

From Slate • Mar. 17, 2020

I expected Kilvin might have padded the price a little, which rankled my pride a bit, but I was in no position to look a gift horse in the mouth.

From "The Name of the Wind" by Patrick Rothfuss