(chiefly Britain) A letter written to a newspaper editor, politician, etc., expressing eccentric views; such a letter is often stereotyped as being handwritten in green ink, characterized by the frequent use of capital letters and underlining, and lengthy.

(chiefly Britain) Collectively, those people who write letters to newspaper editors, politicians, etc., expressing eccentric views; the letters are often stereotyped as being handwritten in green ink, characterized by the frequent use of capital letters and underlining, and lengthy.

plural of green-ink letter

Alternative form of green-ink brigade