Why (?), adv. [OE. whi, why, AS. hwī, hw&unr_;, instrumental case of hwā, hwæt; akin to Icel. hvī why, Dan. & Sw. hvi; cf. Goth. hw&unr_;. &unr_;. See Who.]
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1. For what cause, reason, or purpose; on what account; wherefore; -- used interrogatively. See the Note under What, pron., 1.
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Turn ye, turn ye from your evil ways; for why will ye die, O house of Israel? Ezek. xxxiii. 11.
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2. For which; on account of which; -- used relatively.
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No ground of enmity between us known
Why he should mean me ill or seek to harm. Milton.
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Turn the discourse; I have a reason why
I would not have you speak so tenderly. Dryden.
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3. 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.
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&hand_; 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.
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If her chill heart I can not move,
Why, I'll enjoy the very love. Cowley.
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Sometimes, also, it is used as a noun.
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The how and the why and the where. Goldsmith.
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For why, because; why. See Forwhy. [Obs. or Colloq.]
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