Source : Webster's Revised Unabridged Dictionary (1913)

Social \So"cial\, a. [L. socialis, from socius a companion; akin
   to sequi to follow: cf. F. social. See {Sue} to follow.]
   1. Of or pertaining to society; relating to men living in
      society, or to the public as an aggregate body; as, social
      interest or concerns; social pleasure; social benefits;
      social happiness; social duties. ``Social phenomena.''
      --J. S. Mill.

   2. Ready or disposed to mix in friendly converse;
      companionable; sociable; as, a social person.

   3. Consisting in union or mutual intercourse.

            Best with thyself accompanied, seek'st not Social
            communication.                        --Milton.

   4. (Bot.) Naturally growing in groups or masses; -- said of
      many individual plants of the same species.

   5. (Zo["o]l.)
      (a) Living in communities consisting of males, females,
          and neuters, as do ants and most bees.
      (b) Forming compound groups or colonies by budding from
          basal processes or stolons; as, the social ascidians.

   {Social science}, the science of all that relates to the
      social condition, the relations and institutions which are
      involved in man's existence and his well-being as a member
      of an organized community; sociology. It concerns itself
      with questions of the public health, education, labor,
      punishment of crime, reformation of criminals, and the
      like.

   {Social whale} (Zo["o]l.), the blackfish.

   {The social evil}, prostitution.

   Syn: Sociable; companionable; conversible; friendly;
        familiar; communicative; convival; festive.

Source : WordNet®

social
     adj 1: relating to human society and its members; "social
            institutions"; "societal evolution"; "societal
            forces"; "social legislation" [syn: {societal}]
     2: living together or enjoying life in communities or organized
        groups; "human beings are social animals"; "spent a
        relaxed social evening"; "immature social behavior" [ant:
        {unsocial}]
     3: relating to or belonging to or characteristic of high
        society; "made fun of her being so social and high-toned";
        "a social gossip colum"; "the society page"
     4: composed of sociable people or formed for the purpose of
        sociability; "a purely social club"; "the church has a
        large social hall"; "a social director"
     5: (of birds and animals) tending to move or live together in
        groups or colonies of the same kind; "ants are social
        insects"; "the herding instinct in sheep or cattle";
        "swarming behavior in bees" [syn: {herding(a)}, {swarming(a)}]
     6: marked by friendly companionship with others; "a social cup
        of coffee"

social
     n : a party of people assembled to promote sociability and
         communal activity [syn: {sociable}, {mixer}]