What does "beware" mean?

Beware: To have a special regard; to heed. [Obs.] Behold, I send an Angel before thee. . . . Beware of him, and obey his voice. Ex. xxiii. 20, 21. Note: This word is a compound from be and the Old English ware, now wary, which is an adjective. "Be ye war of false prophetis." Wyclif, Matt. vii.

Additional senses

  1. 2.It is used commonly in the imperative and infinitive modes, and with such auxiliaries (shall, should, must, etc.) as go with the infinitive.
  2. 3.To avoid; to take care of; to have a care for. [Obs.] "Priest, beware your beard." Shak. To wish them beware the son. Milton.

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