For what cause or reason. Turn ye, turn ye, for why will ye die? Jeremiah 27:13.

For which reason or cause. No ground of enmity, why he should mean me ill.

For what reason or cause; for which; relatively. Turn the discourse; I have a reason why I would not have you speak so tenderly.

It is used sometimes emphatically, or rather as a expletive. If her chill heart I cannot move, why, Ill enjoy the very love.