Source : Webster's Revised Unabridged Dictionary (1913)

Slave \Slave\, n. [Cf. F. esclave, D. slaaf, Dan. slave, sclave,
   Sw. slaf, all fr. G. sklave, MHG. also slave, from the
   national name of the Slavonians, or Sclavonians (in LL. Slavi
   or Sclavi), who were frequently made slaves by the Germans.
   See {Slav}.]
   1. A person who is held in bondage to another; one who is
      wholly subject to the will of another; one who is held as
      a chattel; one who has no freedom of action, but whose
      person and services are wholly under the control of
      another.

            thou our slave, Our captive, at the public mill our
            drudge?                               --Milton.

   2. One who has lost the power of resistance; one who
      surrenders himself to any power whatever; as, a slave to
      passion, to lust, to strong drink, to ambition.

   3. A drudge; one who labors like a slave.

   4. An abject person; a wretch. --Shak.

   {Slave ant} (Zo["o]l.), any species of ants which is captured
      and enslaved by another species, especially {Formica
      fusca} of Europe and America, which is commonly enslaved
      by {Formica sanguinea}.

   {Slave catcher}, one who attempted to catch and bring back a
      fugitive slave to his master.

   {Slave coast}, part of the western coast of Africa to which
      slaves were brought to be sold to foreigners.

   {Slave driver}, one who superintends slaves at their work;
      hence, figuratively, a cruel taskmaster.

   {Slave hunt}.
      (a) A search after persons in order to reduce them to
          slavery. --Barth.
      (b) A search after fugitive slaves, often conducted with
          bloodhounds.

   {Slave ship}, a vessel employed in the slave trade or used
      for transporting slaves; a slaver.

   {Slave trade}, the business of dealing in slaves, especially
      of buying them for transportation from their homes to be
      sold elsewhere.

   {Slave trader}, one who traffics in slaves.

   Syn: Bond servant; bondman; bondslave; captive; henchman;
        vassal; dependent; drudge. See {Serf}.

Source : WordNet®

Formica fusca
     n : an ant frequently enslaved