on a first-name basis

1. Quite familiar and friendly, as in Practically all the guests were on a first-name basis. This idiom alludes to the fact that using a person's given name betokens familiarity. [Second half of 1900s]

Example Sentences

He was quickly on a first-name basis with Paul Rudolph, the intimidating head of the school, and the influential art historian Vincent Scully.

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Many of the players are on a first-name basis with the city, and if they aren’t, they’re identified by a nickname.

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She’s a diminutive talent on a first-name basis with South Carolina coach Dawn Staley.

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It was only his first game in purple and gold since being stolen from the Dallas Mavericks nine days ago, yet Luka Doncic and the Laker fans were already on a first-name basis.

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As Cressy drove up the street, Daryl Gross stopped to talk with her neighbor whom she didn’t quite know on a first-name basis.

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