as (adv., conj., pron.)

c. 1200, worn-down form of Old English alswa "quite so, wholly so," literally "all so" (see also), fully established by c. 1400. Equivalent to so; any distinction in use is purely idiomatic. Related to German als "as, than," from Middle High German also.

Phrase as well "just as much" is recorded from late 15c.; the phrase also can imply "as well as not," "as well as anything else." Phrase as if, in Kantian metaphysics (translating German als ob), introducing a supposition not to be taken literally, is from 1892; as an interjection of incredulity (as if!; i.e. "as if that really could happen") is attested from 1995. It duplicates Latin quasi. Phrase as it were "as if it were so" is attested from late 14c.

updated on December 05, 2018

Definitions of as from WordNet
as (n.)
a United States territory on the eastern part of the island of Samoa;
Synonyms: American Samoa / Eastern Samoa
as (adv.)
to the same degree (often followed by `as');
he is every bit as mean as she is
birds were singing and the child sang as sweetly
sang as sweetly as a nightingale
Synonyms: equally / every bit
As (n.)
a very poisonous metallic element that has three allotropic forms; arsenic and arsenic compounds are used as herbicides and insecticides and various alloys; found in arsenopyrite and orpiment and realgar;
Synonyms: arsenic / atomic number "
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