interrogative. For what reason, why (= senses 1 2).

in various obsolete senses of of, v.: esp. From what source, whence; to what purpose, what‥for; for what reason, wherefore.

To what end? for what purpose? for what reason? wherefore? what‥for? Obsolete exc. archaic.

For what cause or reason? on what account? why? (Frequently with ellipsis; often coupled with why for emphasis.)

interrogative: At what? rare.

In pregnant use = How is it that? How comes it that? Why? Obsolete.

interrogative. = whereto, adv. 2. Obsolete.

Upon what? = whereon, adv. 1; †in early use = at what? about or concerning what? upon what ground, wherefore?

For what reason? why? (by, prep. 36). Obsolete.

‘What for?’; why? for what reason?