in-joke
US /ˈɪn.dʒoʊk/
UK /ˈɪn.dʒoʊk/

1.
lelucon internal, lelucon pribadi
a joke that is understood only by a small group of people who are familiar with a particular subject or situation
:
•
Their conversation was full of in-jokes that I didn't understand.
Percakapan mereka penuh dengan lelucon internal yang tidak saya mengerti.
•
You had to be there to get the in-joke.
Kamu harus ada di sana untuk memahami lelucon internal itu.