spar·er /ˈspɛrɚ/ 名詞
  節省物質
  Spar·er n. One who spares.
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  Spare, a. [Compar. Sparer superl. Sparest; -- not used in all the senses of the word.]
  1. Scanty; not abundant or plentiful; as, a spare diet.
  2. Sparing; frugal; parsimonious; chary.
     He was spare, but discreet of speech.   --Carew.
  3. Being over and above what is necessary, or what must be used or reserved; not wanted, or not used; superfluous; as, I have no spare time.
     If that no spare clothes he had to give.   --Spenser.
  4. Held in reserve, to be used in an emergency; as, a spare anchor; a spare bed or room.
  5. Lean; wanting flesh; meager; thin; gaunt.
     O, give me the spare men, and spare me the great ones.   --Shak.
  6. Slow. [Obs. or prov. Eng.]
  sparer
       n : someone who refrains from injuring or destroying