letter box

Từ điển WordNet v3.1 - WordNet Dictionary

noun

1. a numbered compartment in a post office where mail is put to be called for
• Syn:
Post-Office box, PO Box, POB, call box
• Hypernyms:
compartment
2. public box for deposit of mail
• Syn:
postbox, mailbox
• Hypernyms:
maildrop
• Hyponyms:
pillar box
3. a private box for delivery of mail
• Syn:
mailbox
• Hypernyms:
box