[syn: pamperer, spoiler, coddler, mollycoddler]
4.  an airfoil mounted on the rear of a car to reduce lift at high speeds; 
5.  a hinged airfoil on the upper surface of an aircraft wing that is raised to reduce lift and increase drag; 
The Collaborative International Dictionary of English v.0.48:
Spoiler \Spoil"er\ (spoil"[~e]r), n.
   1. One who spoils; a plunderer; a pillager; a robber; a
      despoiler.
      [1913 Webster]
   2. One who corrupts, mars, or renders useless.
      [1913 Webster]
   3. (Aeronautics) A device attached to the wing of an airplane
      or other airfoil, which breaks the smooth flow of air
      during flight and decreases the lift of the airfoil; --
      used to control the attitude of the airplane during
      banking or descent.
      [PJC]
   4. A device attached to a car to decrease lift and increase
      traction, usually shaped as a flat surface and attached
      above the rear of the car, and working on the same
      principal as the aircraft spoiler[3].
      [PJC]
WordNet (r) 3.0 (2006):
spoiler
    n 1: a candidate with no chance of winning but who may draw
         enough votes to prevent one of the leading candidates from
         winning
    2: someone who takes spoils or plunder (as in war) [syn:
       plunderer, pillager, looter, spoiler, despoiler,
       raider, freebooter]
    3: someone who pampers or spoils by excessive indulgence [syn:
       pamperer, spoiler, coddler, mollycoddler]
    4: an airfoil mounted on the rear of a car to reduce lift at
       high speeds
    5: a hinged airfoil on the upper surface of an aircraft wing
       that is raised to reduce lift and increase drag
The Jargon File (version 4.4.7, 29 Dec 2003):
spoiler
 n.
    [Usenet]
    1. A remark which reveals important plot elements from books or movies,
    thus denying the reader (of the article) the proper suspense when reading
    the book or watching the movie.
    2. Any remark which telegraphs the solution of a problem or puzzle, thus
    denying the reader the pleasure of working out the correct answer (see also
    interesting). Either sense readily forms compounds like total spoiler,
    quasi-spoiler and even pseudo-spoiler.
    By convention, articles which are spoilers in either sense should contain
    the word ?spoiler? in the Subject: line, or guarantee via various tricks
    that the answer appears only after several screens-full of warning, or
    conceal the sensitive information via rot13, spoiler space or some
    combination of these techniques.
The Free On-line Dictionary of Computing (30 December 2018):
spoiler
   1. A remark which reveals important plot elements
   from books or movies, thus denying the reader (of the article)
   the proper suspense when reading the book or watching the
   movie.
   2. Any remark which telegraphs the solution of a problem or
   puzzle, thus denying the reader the pleasure of working out
   the correct answer (see also interesting).  Either sense
   readily forms compounds like "total spoiler", "quasi-spoiler"
   and even "pseudo-spoiler".
   By convention, Usenet news articles which are spoilers in
   either sense should contain the word "spoiler" in the Subject:
   line, or guarantee via various tricks that the answer appears
   only after several screens-full of warning, or conceal the
   sensitive information via rot13, or some combination of
   these techniques.
   [Jargon File]
   (1995-01-18)