in on sth
involved with or knowing about a particular activity or plan:
He seems to be in on everything that happens at work.
She's trying to get in on a research project organised by the university.

[TahlilGaran] Advanced Learner's Dictionary ▲

in on
1. • in on (something)
joining together for something
We went in on a present for our father for Father's Day.

2. • in on (something/a secret)
told about something, having knowledge of something
I was finally in on the secret about why the supervisor left our company.

[TahlilGaran] English Idioms Dictionary ▲

in on something
1. • in on (something)
joining together for something
We went in on a present for our father for Father's Day.

2. • in on (something/a secret)
told about something, having knowledge of something
I was finally in on the secret about why the supervisor left our company.

[TahlilGaran] English Idioms Dictionary ▲

in on
prep.
1. Joining together for.
The children collected money from their classmates and went in on a present for their teacher.
2. Told about; having knowledge of.
Bob was in on the secret.
The other girls wouldn't let Mary in on what they knew.

[TahlilGaran] English Idioms Dictionary ▲