old boy

plural old boys · alternative OB

1. UKAn alumnus, especially of a public school.
2. A former member of a group.

   Swansea named an unchanged side from their win over West Brom, and the visitors made an encouraging start, with Blues old boy Scott Sinclair prominent - Branislav Ivanovic had to make an important block to halt the winger's run.

   2011 September 24, Aled Williams, “Chelsea 4 - 1 Swansea”, in BBC Sport

3. A man with an established network of friends who assist one another in social and business situations; a good old boy.

   The fact that they have waited to leave messages and have left hand-written evidence indicates to me that they don't believe they are going to be apprehended, that they have friends in 'higher places.' This is a small town. Everybody knows everybody. That 'ol boy' chuminess ^([sic]).

   1983 February 12, Jil Clark, quoting Kiriyo Spooner, “Northampton Lesbians Fight Hate Campaign”, in Gay Community News, volume 10, number 29, page 3

4. UKinformalAn elderly man.

   I got talking to an old boy in the pub, and he told me what the village used to be like in the old days.

5. UKdatedA familiar term of address for a man of any age.

   Listen, old boy, I've got some news.