Category

4 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Category \Cat"e*go*ry\, n.; pl. {Categories}. [L. categoria, Gr.
     ?, fr. ? to accuse, affirm, predicate; ? down, against + ? to
     harrangue, assert, fr. ? assembly.]
     1. (Logic.) One of the highest classes to which the objects
        of knowledge or thought can be reduced, and by which they
        can be arranged in a system; an ultimate or undecomposable


        conception; a predicament.
        [1913 Webster]
  
              The categories or predicaments -- the former a Greek
              word, the latter its literal translation in the
              Latin language -- were intended by Aristotle and his
              followers as an enumeration of all things capable of
              being named; an enumeration by the summa genera
              i.e., the most extensive classes into which things
              could be distributed.                 --J. S. Mill.
        [1913 Webster]
  
     2. Class; also, state, condition, or predicament; as, we are
        both in the same category.
        [1913 Webster]
  
              There is in modern literature a whole class of
              writers standing within the same category. --De
                                                    Quincey.
        [1913 Webster]

From WordNet (r) 2.0 [wn]:

  category
       n 1: a collection of things sharing a common attribute; "there
            are two classes of detergents" [syn: {class}, {family}]
       2: a general concept that marks divisions or coordinations in a
          conceptual scheme

From Moby Thesaurus II by Grady Ward, 1.0 [moby-thes]:

  49 Moby Thesaurus words for "category":
     area, blood, bracket, branch, caste, clan, class, classification,
     department, division, estate, grade, group, grouping, head,
     heading, kin, kind, label, league, level, list, listing, order,
     pigeonhole, position, predicament, race, rank, ranking, rating,
     rubric, section, sector, sept, set, sort, sphere, station, status,
     strain, stratum, subdivision, subgroup, suborder, tier, title,
     type, variety
  
  

From The Free On-line Dictionary of Computing (27 SEP 03) [foldoc]:

  category
       
           A category K is a collection of objects, obj(K), and
          a collection of {morphisms} (or "{arrows}"), mor(K) such that
       
          1. Each morphism f has a "typing" on a pair of objects A, B
          written f:A->B.  This is read 'f is a morphism from A to B'.
          A is the "source" or "{domain}" of f and B is its "target" or
          "{co-domain}".
       
          2. There is a {partial function} on morphisms called
          {composition} and denoted by an {infix} ring symbol, o.  We
          may form the "composite" g o f : A -> C if we have g:B->C and
          f:A->B.
       
          3. This composition is associative: h o (g o f) = (h o g) o f.
       
          4. Each object A has an identity morphism id_A:A->A associated
          with it.  This is the identity under composition, shown by the
          equations id_B o f = f = f o id_A.
       
          In general, the morphisms between two objects need not form a
          {set} (to avoid problems with {Russell's paradox}).  An
          example of a category is the collection of sets where the
          objects are sets and the morphisms are functions.
       
          Sometimes the composition ring is omitted.  The use of
          capitals for objects and lower case letters for morphisms is
          widespread but not universal.  Variables which refer to
          categories themselves are usually written in a script font.
       
          (1997-10-06)