post‧bag /ˈpəʊstbæɡ $ ˈpoʊst-/ noun British English

1. [singular] all the letters received by an important person, television programme etc on a particular occasion:
We’ve had an enormous postbag on the recent programme changes.

2. [countable] a bag for carrying letters, used by the person who delivers them Synonym : mailbag American English

[TahlilGaran] Dictionary of Contemporary English ▲