Warn

1. v. t. To refuse.
2. v. t. To make ware or aware; to give previous information to; to give notice to; to notify; to admonish; hence, to notify or summon by authority; as, to warn a town meeting; to warn a tenant to quit a house.
3. v. t. To give notice to, of approaching or probable danger or evil; to caution against anything that may prove injurious.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.