make eyes (at someone)
idiom

- to look at someone in a way that shows them that you think they are attractive

(Cambridge Dictionary)

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To make eyes is just another way to say that someone is flirting. Technically it's not just the eyes that are "making" something. It has to do with the entire facial expression, a type of body language that shows someone you find them attractive. This idiom is more often than not used in the continuous senses with the -ing suffix (is making, was making, has been making, etc...)

Although slightly different versions, such as throw the eye at, are much older, this particular expression was first recorded in William Makepeace Thackeray's Henry Esmond (1852): "She used to make eyes at the Duke of Marlborough."

Apart from making eyes, you can also "make a face, " which means to make silly expressions with your face in order to make people laugh.

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SYNONYMS

eyeball, give someone the once over, check someone out, flirt with someone, ogle

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Practice OWAD in a conversation

"I believe the waiter was MAKING EYES at you."