sub·scribe 
(səb-scrīb)
(səb-scrīb)v. sub·scribed, sub·scrib·ing, sub·scribes
v.tr.
1. To pledge or contribute (a sum of money).
2.
a. To sign (one's name) at the end of a document, especially to attest to or authenticate it.
b. To sign one's name to (a document) in attestation, testimony, or consent: subscribe a will.
3. To purchase or claim the shares of (a new issue of stock, bonds, or other securities): a bond offering that is fully subscribed.
v.intr.
1.
a. To contract to receive and pay for a certain number of issues of a publication, for access to a website that is protected by a paywall, for tickets to a series of events or performances, or for a utility service, for example.
b. To agree to an ongoing arrangement by which one receives online content, as from a specific website or a specific user on a website.
2. To promise to pay or contribute money: subscribe to a charity.
3. To purchase or claim shares of a new issue of stock, bonds, or other securities: an investor who subscribed for 100 shares.
4. To feel or express hearty approval: I subscribe to your opinion. See Synonyms at assent.
5. To sign one's name to a document.
[Middle English subscriben, to sign, from Latin subscrībere : sub-, sub- + scrībere, to write; see skrībh- in the Appendix of Indo-European roots.]
sub·scriber n.