lock into

US /lɑːk ˈɪntuː/
UK /lɑːk ˈɪntuː/
"lock into" picture
1.

to commit oneself to a particular course of action or situation, often one that is difficult to change

:
We don't want to lock into a long-term contract without careful consideration.
Once you lock into this payment plan, it's hard to change.
2.

to become firmly fixed or engaged with something else, often mechanically

:
The gears need to lock into place for the machine to work properly.
The two pieces will lock into each other with a click.