fit in

Wiktionary

To be physically capable of going into a space.
To find or make a place for:
“Just show up ready for work, and they'll fit you in no matter what your skills are.”
To find or make a place for:
“The dentist said he can't fit me in until Thursday.”
“I don't have time to work on your house today, but I'll fit it in tomorrow.”
To be or become of a like type with others; (especially) to be or become socially accepted.
“The recluse did not fit in at the party.”
“KORRIS: They shunned you. Cursed you. Called you vile names, and you knew not why. Even now do you know why you are driven? Why you cannot relent — or repent — or confess — or abstain? How could you know? There have been no other Klingons to lead you to that knowledge. WORF: Yes — yes — those feelings are still a part of me, but I control them. They do not rule me. KORRIS: Yes, to fit in, the humans demand you change the one thing that you cannot change. But because you cannot — you do. That too is the mark of the warrior.”
(followed by with) To conform, to be suitable.
“I'm afraid that does not fit in with our plans.”
(used alone or followed by with) To be consistent or reconcilable (with other facts or ideas).
“; see also Thesaurus:agree”
“We felt confident about our previous theory, but the results of the latest experiments don't fit in.”