mail (n.1)

"post, letters," c. 1200, "a traveling bag, sack for keeping small articles of personal property," a sense now obsolete, from Old French male "wallet, bag, bundle," from Frankish *malha or some other Germanic source, from Proto-Germanic *malho- (source also of Old High German malaha "wallet, bag," Middle Dutch male "bag"), from PIE *molko- "skin, bag."

The sense was extended to "bag full of letters" (1650s; perhaps via phrases such as a mail of letters, 1654) and "person or vehicle that carries postal matter" (1650s). From thence, to "letters and parcels" generally (1680s) and "the system of transmission by public post" (1690s).

As a newspaper name, by 1789. In 19c. England, mail was letters going abroad, while home dispatches were post. Sense of "a personal batch of letters" is from 1844, originally American English. Mail slot "narrow opening in an exterior door of a building to receive mail delivery" is by 1893, American English. OED defines it as a "letter-slit."

mail (n.2)

"metal ring armor," c. 1300, from Old French maille "link of mail, mesh of net," from Latin macula "mesh in a net," originally "spot, blemish," on notion that the gaps in a net or mesh looked like spots. Its use dates from late Roman times. The favorite armor in Europe 12c.-13c., it was effective, but heavy and costly.

mail (v.)

"send by post," 1828, American English, from mail (n.1). "The usual word in the U.K. is still post" [OED]. Related: Mailed; mailing; mailable. Mailing list "register of addresses" is attested from 1876.

mail (n.3)

"rent, payment," from late Old English mal; see blackmail (n.).

Others are reading

Definitions of mail
mail (n.)
the bags of letters and packages that are transported by the postal service;
mail (n.)
the system whereby messages are transmitted via the post office;
he works for the United States mail service
the mail handles billions of items every day
in England they call mail `the post'
Synonyms: mail service / postal service / post
mail (n.)
a conveyance that transports the letters and packages that are conveyed by the postal system;
mail (n.)
any particular collection of letters or packages that is delivered;
your mail is on the table
Synonyms: post
mail (n.)
(Middle Ages) flexible armor made of interlinked metal rings;
Synonyms: chain mail / ring mail / chain armor / chain armour / ring armor / ring armour
mail (v.)
send via the postal service;
I'll mail you the check tomorrow
Synonyms: get off
mail (v.)
cause to be directed or transmitted to another place;
I'll mail you the paper when it's written
Synonyms: post / send