The Collaborative International Dictionary of English v.0.48:
Authorize \Au"thor*ize\, v. t. [imp. & p. p. Authorized; p.
pr. & vb. n. Authorizing.] [OE. autorize, F. autoriser, fr.
LL. auctorizare, authorisare. See Author.]
1. To clothe with authority, warrant, or legal power; to give
a right to act; to empower; as, to authorize commissioners
to settle a boundary.
2. To make legal; to give legal sanction to; to legalize; as,
to authorize a marriage.
3. To establish by authority, as by usage or public opinion;
to sanction; as, idioms authorized by usage.
4. To sanction or confirm by the authority of some one; to
warrant; as, to authorize a report.
A woman's story at a winter's fire,
Authorized by her grandam. --Shak.
5. To justify; to furnish a ground for. --Locke.
To authorize one's self, to rely for authority. [Obs.]
Authorizing himself, for the most part, upon other
histories. --Sir P.