(defective, transitive, intransitive) To use caution, pay attention to (used both with and without of).

(obsolete) Third-person singular simple present indicative form of beware

(obsolete) simple past tense and past participle of beware

(archaic or nonstandard) present participle of beware

(poetic) Fought over; war-torn.

Used as a warning to a potential buyer of a product about its defects. / (figuratively, by extension, often humorous) Exhortation for the listener to exercise caution.

It is the buyer’s responsibility to ensure the soundness of goods or services prior to his purchase of them.

One should not trust one's enemies.