"something, anything," late 12c., from Old English awiht "aught, anything, something," literally "e'er a whit," from a- "ever" (from Proto-Germanic *aiwi- "ever," extended form of PIE root *aiw- "vital force, life; long life, eternity") + *wihti "thing, anything whatever" (see wight). In Shakespeare, Milton, and Pope, aught and ought occur indiscriminately. Chaucer used aughtwhere (adv.) "anywhere."

"nothing, zero," faulty separation of a naught (see naught). See adder for similar misdivisions.

"in, at, or to any place," late 14c., from any + where. Earlier words in this sense were owhere, oughwhere, aywhere, literally "aught where" (see aught (n.1)).

also *ayu-, Proto-Indo-European root meaning "vital force, life; long life, eternity."

It forms all or part of: age; aught (n.1) "something; anything;" aye (adv.) "always, ever;" Ayurvedic; coetaneous; coeval; each; eon; eternal; eternity; ever; every; ewigkeit; hygiene; longevity; medieval; nay; never; no; primeval; sempiternal; tarnation; utopia. 

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit ayu- "life;" Avestan aiiu "age, life(time);" Greek aiōn "age, vital force; a period of existence, a lifetime, a generation; a long space of time," in plural, "eternity;" Latin aevum "space of time, eternity;" Gothic aiws "age, eternity," Old Norse ævi "lifetime," German ewig "everlasting," Old English a "ever, always."  

"zero, cipher," 1844, probably a misdivision of a nought (see nought; for misdivision, see N); the meaning probably was influenced by aught "anything."

Proto-Indo-European root meaning "not."

It forms all or part of: a- (3) "not, without;" abnegate; ahimsa; an- (1) privative prefix; annihilate; annul; aught (n.2) "zero, nothing;" deny; hobnob; in- (1) "not, opposite of, without;" ixnay; naught; naughty; nay; nefarious; negate; neglect; negligee; negotiate; neither; nepenthe; nescience; nescient; neuter; never; nice; nihilism; nihility; nil; nill; nimiety; nix; no; non-; none; nonplus; nor; not; nothing; null; nullify; nulliparous; renegade; renege; un- (1) prefix of negation; willy-nilly.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit a-, an- "not;" Avestan na "not;" Greek a-, an-, ne- "not;" Latin in- "not," ne "that not;" Old Church Slavonic and Lithuanian ne "not;" Old Irish an-, ni, Cornish ny "not;" Gothic and Old English un- "not."

Old English ahte "owned, possessed," past tense of agan "to own, possess; owe" (see owe). As a past tense of owe, it shared in that word's evolution and meant at times in Middle English "possessed" and "under obligation to pay." It has been detached from owe since 17c., though he aught me ten pounds is recorded as active in East Anglian dialect c. 1825. As an auxiliary verb expressing duty or moral obligation (the main modern use, attested from late 12c.), it represents the past subjunctive.

Ought, Should. Ought is the stronger, expressing especially obligations of duty, with some weaker use in expressing interest or necessity: as, you ought to know, if any one does. Should sometimes expresses duty: as, we should be careful of others' feelings; but generally expresses propriety, expediency, etc.: as, we should dot our i's and cross our t's. [Century Dictionary, 1895]