in-joke

[in-johk]

noun

a joke that can be understood or appreciated only by the members of a limited group of people.

Origin of in-joke

First recorded in 1960–65
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Word Origin and History for in-joke
n.

1964, from in + joke.

Online Etymology Dictionary, © 2010 Douglas Harper