grin like a Cheshire cat

Idioms  

1. Smile broadly, especially in a self-satisfied way. For example, John ended the set with a beautiful serve, an ace, and couldn't help grinning like a Cheshire cat. The ultimate origin of this expression, appearing in print since the late 1700s, is disputed, but its most famous exponent was Lewis Carroll, in whose Alice's Adventures in Wonderland the grinning cat gradually vanished from view, with its grin the last part to vanish.

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Example Sentences

When the conversation is flowing effortlessly about a niche show you both like, you can’t help but grin like a Cheshire cat.

From Los Angeles Times

You’ve got a tough persona, like a side of beef, and you’re aroused and stimulated, with an ear-to-ear grin, like a Cheshire cat, and you’re rethinking your entire formless life, your entire being is filled with a whiff of this heady ambrosia.

From New York Times

The English-born air ace greeted him with a grin like a Cheshire cat.

From Project Gutenberg

"You grin like a Cheshire cat," she remarked.

From Project Gutenberg

That some of this cheerfulness may be simply animal is true, and that a man may be a dullard and yet sit and "grin like a Cheshire cat;" but we are not speaking of grinning.

From Project Gutenberg