What does "why" mean?

Why: 2. For which; on account of which; -- used relatively. No ground of enmity between us known Why he should mean me ill or seek to harm. Milton. Turn the discourse; I have a reason why I would not have you speak so tenderly. Dryden.

Additional senses

  1. 2.The reason or cause for which; that on account of which; on what account; as, I know not why he left town so suddenly; -- used as a compound relative. Note: Why is sometimes used as an interjection or an expletive in expression of surprise or content at a turn of affairs; used also in calling. "Why, Jessica!" Shak. If her chill heart I can not move, Why, I'll enjoy the very love. Cowley. Sometimes, also, it is used as a noun. The how and the why and the where. Goldsmith. For why, because; why. See Forwhy. [Obs. or Colloq.]
  2. 3.A young heifer. [Prov. Eng.] Grose.

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