1. [v]  mark with one's signature; write one's name (on); "She signed the letter and sent it off"; "Please sign here"
2. [v]  adopt as a belief; "I subscribe to your view on abortion"
3. [v]  receive or obtain by regular payment; "We take the Times every day"
4. [v]  offer to buy, as of stocks and shares; "The broker subscribed 500 shares"
5. [v]  pay (an amount of money) as a contribution to a charity or service, esp. at regular intervals; "I pledged $10 a month to my favorite radio station"

1. \Sub*scribe"\, v. t. [imp. & p. p. {Subscribed}; p.
   pr. & vb. n. {Subscribing}.] [L. subscribere, subscriptum;
   sub under + scribere to write: cf. F. souscrire. See
   {Scribe}.]
   1. To write underneath, as one's name; to sign (one's name)
      to a document.
            [They] subscribed their names under them. --Sir T.
                                                  More.
   2. To sign with one's own hand; to give consent to, as
      something written, or to bind one's self to the terms of,
      by writing one's name beneath; as, parties subscribe a
      covenant or contract; a man subscribes a bond.
            All the bishops subscribed the sentence. --Milman.
   3. To attest by writing one's name beneath; as, officers
      subscribe their official acts, and secretaries and clerks
      subscribe copies or records.
   4. To promise to give, by writing one's name with the amount;
      as, each man subscribed ten dollars.
   5. To sign away; to yield; to surrender. [Obs.] --Shak.
   6. To declare over one's signature; to publish. [Obs.]
            Either or must shortly hear from him, or I will
            subscribe him a coward.               --Shak.
   

2. \Sub*scribe"\, v. i.
   1. To sign one's name to a letter or other document. --Shak.
   2. To give consent to something written, by signing one's
      name; hence, to assent; to agree.
            So spake, so wished, much humbled Eve; but Fate
            Subscribed not.                       --Milton.
   3. To become surely; -- with for. [R.] --Shak.
   4. To yield; to admit one's self to be inferior or in the
      wrong. [Obs.]
            I will subscribe, and say I wronged the duke.
                                                  --Shak.
   5. To set one's name to a paper in token of promise to give a
      certain sum.
   6. To enter one's name for a newspaper, a book, etc.
   

To request to receive messages posted to a mailing list or newsgroup. In contrast to the mundane use of the word this is often free of charge.