letterbox
/ˈlɛtərˌbɒks/Definitions
1. noun
A receptacle for mail at the entrance of a house, typically with a hinged lid that can be opened to deposit mail.
“She forgot to check the letterbox and missed the important delivery.”
2. verb
To deliver mail to a letterbox, especially in the absence of the addressee.
“The mailman had to letterbox the package since nobody was home.”