A means of communication (6)

I think it could be either:

Which length description are you looking for?:

letter

(Other definitions for letter that I've seen before include "Piece of correspondence" , "Character; missive" , "A, B or C, for example" , "Alphabetic character" , "Epistle, missive" .)

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.