An open letter is a type of written communication that is addressed to a wide audience, usually published in a newspaper or magazine. It is typically written by an individual or group of people and is intended to express their opinion on a particular issue. The term 'open letter' comes from the fact that it is not addressed to a specific person or organization, but rather to the public at large. SPREAD is a six-letter word that means to distribute widely or to make known. In the context of an open letter, SPREAD would refer to the act of making the letter known to the public.