in-joke

US /ˈɪn.dʒoʊk/
UK /ˈɪn.dʒoʊk/
"in-joke" picture
1.

piada interna, piada particular

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.
A conversa deles estava cheia de piadas internas que eu não entendia.
You had to be there to get the in-joke.
Você tinha que estar lá para entender a piada interna.