Why

1. (adv.) For what cause, reason, or purpose; on what account; wherefore; -- used interrogatively. See the Note under What, pron., 1.

2. (adv.) For which; on account of which; -- used relatively.

3. (n.) 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.

4. (n.) A young heifer.

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