as

Definitions

General English

  • conjunction at the same time that something else happens
  • preposition in a particular job
  • preposition because of being a particular type of person
  • preposition in a particular way

Information & Library Science

Electronics

  • chemical symbol forarsenic
    (written as As)
  • abbreviation forattosecond
  • abbreviation forattosiemens
    (written as aS)
  • abbreviation forabsiemens
    (written as aS)
  • 10-18 second. It is a unit of time measurement. Its abbreviation is as, or asec.
  • 10-18 siemens. It is a unit of conductance. Its abbreviation is aS.

Origin & History of “as”

Ultimately, as is the same word as also. Old English alswā ‘in just this way’ was used in some contexts in which modern English would use as, and as it was weakly stressed in such contexts it gradually dwindled to als or ase and finally to as.
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