Mail is anything that's delivered to your mail box or post office box — letters, bills, packages, magazines, or anything else that's sent through the postal service. Email is the internet's version of mail.

Mail carriers' bags are full of mail, and the system that allows this mail to be delivered all over the world is also called the mail. As a verb, to mail something is to send it via this system: when you write a letter, address and stamp it, and put it in a mailbox, you mail it. Mail is also the name for a type of light armor made of interlocking metal rings. If you read a novel about a knight wearing mail, he's wearing this type of armor — he's not covered in letters!

Definitions of mail
  1. noun
    the bags of letters and packages that are transported by the postal service
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    1st class, 1st-class mail, first class, first-class mail
    mail that includes letters and postcards and packages sealed against inspection
    express, express mail
    mail that is distributed by a rapid and efficient system
    parcel post
    postal service that handles packages
    bulk mail
    mail consisting of large numbers of identical items (circulars or advertisements) sent to individual addresses at less than 1st-class rates and paid for in one lot
    third class, third-class mail
    mail consisting of printed matter qualifying for reduced postal rates
    letters and packages that are transported by aircraft
    air mail
    mail that is sent by air transport
    surface mail
    mail that is sent by land or sea
    registered mail, registered post
    mail that is registered by the post office when sent in order to assure safe delivery
    special delivery
    mail that is delivered by a special carrier (for an additional charge)
    pony express
    express mail carried by relays of riders on horseback; especially between Missouri and California around 1860
    junk mail
    third-class mail consisting of advertising and often addressed to `resident' or `occupant'
    communication by the exchange of letters
    type of:
    a communication (usually brief) that is written or spoken or signaled
  2. noun
    any particular collection of letters or packages that is delivered
    “your mail is on the table”
    synonyms: post
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    fan mail
    mail sent to public figures from their admirers
    hate mail
    mail that expresses the writer's dislike or hatred (usually in offensive language)
    mail sent by a sender at one time
    type of:
    accumulation, aggregation, assemblage, collection
    several things grouped together or considered as a whole
  3. noun
    the system whereby messages are transmitted via the post office
    “the mail handles billions of items every day”
    “he works for the United States mail service”
    “in England they call mail `the post'”
    synonyms: mail service, post, postal service
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    airmail, airpost
    a system of conveying mail by aircraft
    snail mail
    any mail that is physically delivered by the postal service
    RFD, rural free delivery
    free government delivery of mail in outlying country areas
    type of:
    communicating, communication
    the activity of communicating; the activity of conveying information
  4. noun
    a conveyance that transports the letters and packages that are conveyed by the postal system
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    type of:
    conveyance, transport
    something that serves as a means of transportation
  5. verb
    send via the postal service
    “I'll mail you the check tomorrow”
    synonyms: get off
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    send by special mail that goes through diplomatic channels
    type of:
    send, send out
    to cause or order to be taken, directed, or transmitted to another place
  6. verb
    cause to be directed or transmitted to another place
    “I'll mail you the paper when it's written”
    synonyms: post, send
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    send by rapid transport or special messenger service
    send or transport by airmail
    send by registered mail
    send by express mail or courier
    type of:
    move from one place to another
  7. noun
    (Middle Ages) flexible armor made of interlinked metal rings
    synonyms: chain armor, chain armour, chain mail, ring armor, ring armour, ring mail
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    a medieval coat of chain mail consisting of metal rings sewn onto leather or cloth
    (Middle Ages) a light sleeveless coat of chain mail worn under the hauberk
    byrnie, hauberk
    a long (usually sleeveless) tunic of chain mail formerly worn as defensive armor
    gusset, voider
    a piece of chain mail covering a place unprotected by armor plate
    type of:
    body armor, body armour, cataphract, coat of mail, suit of armor, suit of armour
    armor that protects the wearer's whole body
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