noun · common

co-uncle

co-uncle · co-uncles

зять, свояк

Schwager, Schwippschwager

Of a man, an uncle of one's niece or nephew who is not one's brotherOf a man, an uncle of one's niece or nephew who is not one's brother; a co-brother-in-law as common uncle to the children of two men's married siblings.

Meaning

2 senses

Of a man, an uncle of one's niece or nephew who is not one's brother; a co-brother-in-law as common uncle to the children of two men's married siblings.
A man's brother, as uncle in common to the children of a third sibling
My nephew came up for the summer with my brother and co-uncle George.