Definition of why :
1. A young heifer.
2. For what cause, reason, or purpose; on what account; wherefore; - used interrogatively. See the Note under What, pron., 1.
3. For which; on account of which; - used relatively.
4. 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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