Used absolutely as an interrogative pronoun.Applied to animals (and sometimes in contempt to persons) with the force of inquiry after the nature or kind: as, what is that running up the tree?Applied to persons: nearly equivalent to who, but having reference to origin or character, rather than to name or identity.Used in various elliptical and incomplete constructions: as, what? equivalent to what did you say? or what is it?Used in exclamation, to express surprise, indignation, etc.Expressing a summons.A general introductory notion, equivalent to ‘well,’ ‘lo,’ ‘now,’ etc., and constituting a mere expletive.Used adjectively and lending an interrogative force to the proposition in which it occurs.Inquiring as to extent or quantity: equivalent to the question how much?Used intensively or emphatically with a force varying from the interrogative to the exclamatory: often followed by the indefinite article: as, what an idea!Elliptical for what say or think you of?A compound relative pronoun, meaning ‘that which,’ or having a value including the simple relative pronoun which with the demonstrative pronoun that preceding: as, “what I have written I have written” (that is, that which I have written I have written). It is no longer used of persons, except in the anomalous phrase but what.What was formerly and in vulgar speech is still used as a simple relative, equivalent to that or which: as, if I had a donkey what wouldn't go.What has also the value of whatever or whoever: as, come what will, I shall be there.Used adjectively, meaning ‘that … which,’ or having compound relative value: as, I know what book you mean (that is, I know that book which you mean); he makes the most of what money he has (that is, he makes the most of that money which he has): applied to persons and things.What sort of; such … as.Any who or which; whatever; whoever.How much.Something; anything: obsolete except in such colloquial phrases as I'll tell you what (by abbreviation for what it is, what I think, or the like).A thing; a portion; an amount; a bit: as, a little what.Why?To what degree? in what respect?How; how greatly; to what an extent or degree; how remarkably: exclamatory and intensive.With omission of the second what (so frequently):So much as; so far as.ThatIn the phrase but what: but that; that … not.Quick; sharp; bold.