Expression: avoir un cheveu sur la langue

Meaning: to have a lisp

Literal translation: to have a hair on the tongue

Register: informal

Notes: The French expression avoir un cheveu sur la langue can be shortened to simply avoir un cheveu. It's an informal synonym of zézayer - to lisp, to have a lisp, to speak with a lisp. The idea behind this expression is that the hair is interfering with the tongue and thus causing the lisp.

Example:

C'est un peu difficile de comprendre Martin au téléphone, parce qu'il a un cheveu sur la langue.
It's kind of hard to understand Martin on the phone, because he lisps.

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