Meaning

noun a written message addressed to a person or organization

noun the conventional characters of the alphabet used to represent speech

noun owner who lets another person use something (housing usually) for hire

originFrom Middle English letter, lettre, from Old French letre, from Latin littera (“letter of the alphabet"; in plural, "epistle”). Displaced Old English bōcstæf (literally “book staff”) in sense 1 and ǣrendġewrit (literally “message writing”) in sense 2.

Etymology from Wiktionary, CC BY-SA 3.0