gra·tu·itous /grəˈtuətəs, ˈtju-/
  (a.)免費的,無理由的
  Gra·tu·i·tous a.
  1. Given without an equivalent or recompense; conferred without valuable consideration; granted without pay, or without claim or merit; not required by justice.
     We mistake the gratuitous blessings of Heaven for the fruits of our own industry.   --L'Estrange.
  2. Not called for by the circumstances; without reason, cause, or proof; adopted or asserted without any good ground; as, a gratuitous assumption.
     Acts of gratuitous self-humiliation.   --De Quincye.
  -- Gra*tu*i*tous*ly, adv. -- Gra*tu*i*tous*ness, n.
  ◄ ►
  gratuitous
       adj 1: without cause; "a gratuitous insult"
       2: costing nothing; "complimentary tickets" [syn: complimentary,
           costless, free, gratis(p)]
       3: unnecessary and unwarranted; "a strikers' tent camp...was
          burned with needless loss of life" [syn: needless, uncalled-for]