hollow something out

Từ điển Oxford Advanced Learner 8th

ˌhollow sthˈout derived
1. to make a hole in sth by removing part of it
•Hollow out the cake and fill it with cream.
•a gun concealed in a hollowed-out book
2. to form sth by making a hole in sth else
•The cave has been hollowed out of the mountainside.
Main entry: ↑hollow_derived