Snail mail is a
derogatory retronym — named after the
snail with its proverbially slow
speed — used to refer to letters and carried by conventional
postal delivery services. The phrase refers to the lag-time between dispatch of a letter and its receipt, versus the virtually instantaneous dispatch and delivery of its electronic equivalent,
e-mail. It is also known, more neutrally, as paper mail, postal mail, or land mail.
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term (slightly pejorative) for conventional mail when compared with e-mail or voice-mail.