LifestyleDated, Slang A fan who is a prolific writer of letters to periodicals.
Nowadays a letter-hack says things simply, which is, after all, the best way. Take any good story. You don't find long, stilted sentences with long-winded descriptions (which was one reason I put ‘The Dimension of Chance’ last). So listen and learn, letter-hacks.1946 Fall, Tom Jewett, Startling Stories, volume 14, number 2, page 102:
LETTERHACK - An actifan who specializes in writing letters for zines. One of the simplest and yet the most effective phases of fanac. Give the letterhack a ream of paper, stamps, and one or two other letterhacks for him to argue with, and he will keep happy and tractable for months.1958, Ralph Merridette Holland, Ghu's Lexicon, page 12:
LifestyleDated, Slang To write letters to periodicals very frequently.
It was in those letter columns that I was first exposed to the concept of fandom. Letterhacking was in high bloom in 1951; the letter columns were filled with chatty letters from all sorts of people, the names of whom I soon came to recognize.1976 November, Ted White, “Twenty Five Years? That's--”, in Science-Fiction Five-Yearly, number 6, page 23: