on a first-name basis

Idioms  

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]

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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.

From The Wall Street Journal

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

From Los Angeles Times

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

From Los Angeles Times

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.

From Los Angeles Times

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.

From Los Angeles Times