1. To clothe with authority, warrant, or legal power; to give a right to act; to empower; as, to authorise commissioners to settle a boundary.
2. To make legal; to give legal sanction to; to legalize; as, to authorise a marriage.
3. To establish by authority, as by usage or public opinion; to sanction; as, idioms authorised by usage.
4. To sanction or confirm by the authority of some one; to warrant; as, to authorise a report. A woman's story at a winters fire, Authorised by her grandam. (Shak)
5. To justify; to furnish a ground for.
Origin: oe. Autorize, f. Autoriser, fr. LL. Auctorizare, authorisare. See Author.