n.

1. 減少；削減[U][C][（+in）]
   reduction of household expenses

   家用開支的削減

2. 縮小[U][C][（+in）]
3. 下降，降低；降級[U][（+to）]
   reduction of an embassy to a liaison office

   大使館降級為聯絡處

4. 縮圖，縮版[C]
5. 轉換，變化[U][（+to）]
   reduction to ashes

   化為灰燼

6. 歸納；簡化[U][（+to）]
7. 【數】簡化，約化[U][C]
8. 【化】還原（作用）[U][C]

n.

1. the action of reducing.
   ▸the amount by which something is reduced.
2. an arrangement of an orchestral score for piano or a smaller group of performers.
3. a smaller copy of a picture or photograph.
4. a thick and concentrated liquid or sauce.