Meaning 1 · most common
make a short visit
to visit a place or person for a short time, usually casually and without much planning
Example
I'll pop in on my way home and see how your mum's doing.
pop in — 2 meanings
One phrase, 2 meanings. Learn them one at a time, then test yourself.
phrasal verb2 meanings
Meaning 2
put something somewhere quickly
To pop something in means to put it somewhere quickly and easily.
Example
A: What should I do with these forms?
B: Just pop them in the envelope.
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