Originally, an interrogative pronoun, later, a
relative pronoun also; -- used always substantively, and either as singular
or plural. See the Note under
What,
pron., 1. As
interrogative pronouns,
who and
whom ask the question: What
or which person or persons?
Who and
whom, as relative
pronouns (in the sense of
that), are properly used of persons
(corresponding to
which, as applied to things), but are sometimes,
less properly and now rarely, used of animals, plants, etc.
Who and
whom, as compound relatives, are also used especially of persons,
meaning the person that; the persons that; the one that; whosoever.
In celebration of Noah Webster's Birthday (October 16, 2009), we have prepared an updated website. 
, interrogative pron., neut.
hwæt; akin to OFries. hwa, neut. hwet, OS.
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