Real Dictionary

mail
The mail is the public service or system by which letters and parcels are collected and delivered.
You can refer to letters and parcels that are delivered to you as mail.
verb: If you mail a letter or parcel to someone, you send it to them by putting it in a post box or taking it to a post office.
verb: To mail a message to someone means to send it to them by means of email or a computer network.

mail in American English 1
a bag or piece of baggage
noun: letters, packages, etc., that are sent or delivered by means of the postal system

mail in American English 2
flexible body armor made of small, overlapping metal rings, loops of chain, or scales
to cover or protect with or as with mail
noun: flexible armor of interlinked rings
transitive verb: to clothe or arm with mail

mail in American English 3
rent or payment of any kind
noun: monetary payment or tribute, esp. rent or tax

mail in British English 1
to send by mail
noun: letters, packages, etc, that are transported and delivered by the post office

mail in British English 2
noun: a type of flexible armour consisting of riveted metal rings or links
verb: to clothe or arm with mail

mail in British English 3
noun: a monetary payment, esp of rent or taxes

mail in British English 4
noun: a rumour or report, esp a racing tip