1. [n]  a room in a hospital equipped for the performance of surgical operations; "great care is taken to keep the operating rooms aseptic"
2. [n]  a state in northwestern United States on the Pacific

1. \-or\ [L. -or: cf. OF. -or, -ur, -our, F. -eur.]
   1. A noun suffix denoting an act; a state or quality; as in
      error, fervor, pallor, candor, etc.
   2. A noun suffix denoting an agent or doer; as in auditor,
      one who hears; donor, one who gives; obligor, elevator. It
      is correlative to -ee. In general -or is appended to words
      of Latin, and -er to those of English, origin. See {-er}.
   

2. \Or\, conj. [OE. or, outher, other, auther, either, or, AS.
   [=a]w?er, contr. from [=a]hw[ae]?er; [=a] aye + hw[ae]?er
   whether. See {Aye}, and {Whether}, and cf. {Either}.]
   A particle that marks an alternative; as, you may read or may
   write, -- that is, you may do one of the things at your
   pleasure, but not both. It corresponds to either. You may
   ride either to London or to Windsor. It often connects a
   series of words or propositions, presenting a choice of
   either; as, he may study law, or medicine, or divinity, or he
   may enter into trade.
         If man's convenience, health, Or safety interfere, his
         rights and claims Are paramount.         --Cowper.
   Note: Or may be used to join as alternatives terms expressing
         unlike things or ideas (as, is the orange sour or
         sweet?), or different terms expressing the same thing
         or idea; as, this is a sphere, or globe.
   Note: Or sometimes begins a sentence. In this case it
         expresses an alternative or subjoins a clause differing
         from the foregoing. ``Or what man is there of you, who,
         if his son shall ask him for a loaf, will give him a
         stone?'' --Matt. vii. 9 (Rev. Ver. ). Or for either is
         archaic or poetic.
               Maugre thine heed, thou must for indigence Or
               steal, or beg, or borrow thy dispence. --Chaucer.
   

3. \Or\, prep. & adv. [AS. ?r ere, before. [root]204. See {Ere},
   prep. & adv.]
   Ere; before; sooner than. [Obs.]
         But natheless, while I have time and space, Or that I
         forther in this tale pace.               --Chaucer.
   {Or ever}, {Or ere}. See under {Ever}, and {Ere}.
   

4. \Or\, n. [F., fr. L. aurum gold. Cf. {Aureate}.] (Her.)
   Yellow or gold color, -- represented in drawing or engraving
   by small dots.
   

The Boolean function which is true if any of its arguments are true. Its truth table is:

 A | B | A OR B
 --+---+---------
 F | F |    F
 F | T |    T
 T | F |    T
 T | T |    T