reduce

decrease, diminish, lessen, reduce, dwindle

这些词的共同含义是“减少，变少”。
decrease: 指逐渐地、不断地减少。
diminish: 侧重大小、数量和重要性的不断减小，强调减小的部分。
lessen: 普通用词，与decrease近义。指数目、程度、价值、实力等的减少。
reduce: 普通用词，含义广。指数量、程度的降低或减少。
dwindle: 与decrease同义，指逐渐减小，但强调变得越来越少终至全无。

动词 reduce:

1. cut down on; make a reduction in
   同义词：cut down, cut back, trim, trim down, trim back, cut, bring down
2. make less complex
3. bring to humbler or weaker state or condition
4. simplify the form of a mathematical equation of expression by substituting one term for another
5. lower in grade or rank or force somebody into an undignified situation
6. be the essential element
   同义词：come down, boil down
7. reduce in size; reduce physically
   同义词：shrink
8. lessen and make more modest
9. make smaller
   同义词：scale down
10. to remove oxygen from a compound, or cause to react with hydrogen or form a hydride, or to undergo an increase in the number of electrons
    同义词：deoxidize, deoxidise
11. narrow or limit
    同义词：tighten
12. put down by force or intimidation
    同义词：repress, quash, keep down, subdue, subjugate
13. undergo meiosis
14. reposition (a broken bone after surgery) back to its normal site
15. reduce in scope while retaining essential elements
    同义词：abridge, foreshorten, abbreviate, shorten, cut, contract
16. be cooked until very little liquid is left
    同义词：boil down, decoct, concentrate
17. cook until very little liquid is left
    同义词：boil down, concentrate
18. lessen the strength or flavor of a solution or mixture
    同义词：dilute, thin, thin out, cut
19. take off weight
    同义词：melt off, lose weight, slim, slenderize, thin, slim down

1. The windows were tinted to reduce the glare.
   窗户上涂上了浅色以减少强光。
2. The manager hasn't worked out a suitable action to reduce the domino effect.
   经理还没有想出一个适当的举措来减少多米诺效应。
3. The government will be looking to reduce inflation by a further two per cent this year.
   政府力求今年把通货膨胀率再减低百分之二。
4. Taking extra vitamins may reduce your liability to colds.
   多吃一些维生素会减少你得感冒的可能性。
5. The new government's prime task is to reduce the level of inflation.
   新政府的主要任务是减低通货膨胀的水平。
6. They were reduced to begging or starving.
   他们穷得不行乞便挨饿。
7. He is trying to reduce the family's expenses.
   他正尽力减少家庭开支。
8. He is reduced almost to a skeleton.
   他瘦得几乎变成了一个骨头架子。

re.duce

v.（动词）
re.duced,re.duc.ing,re.duc.es
v.tr.（及物动词）
To bring down, as in extent, amount, or degree; diminish.See Synonyms at decrease
缩减，减轻：减少，如在范围、数量上或程度上减少；降低参见 decrease
To bring to a humbler, weaker, difficult, or forced state or condition; especially:
使卑下，使薄弱：发展到一个更卑下、虚弱、困难或强迫的地位或状态，特别是：
To gain control of; conquer:
控制，征服：取得对……的控制权；征服：
例句：
.a design to reduce them under absolute despotism.(Declaration of Independence)
.一个使他们沦落到极其专制统治下的计划.(独立宣言)

To subject to destruction:
攻陷，毁坏：遭到毁坏：
例句：
Enemy bombers reduced the city to rubble.
敌人的轰炸机把城市夷为平地

To weaken bodily:
衰弱：身体变虚弱：
例句：
was reduced almost to emaciation.
衰弱到近乎憔悴

To sap the spirit or mental energy of.
精神耗损：侵蚀……的精神或精力
To compel to desperate acts:
迫使：被迫做孤注一掷的举动：
例句：
The Depression reduced many to begging on street corners.
大萧条使许多人沦落到街头乞讨

To lower in rank or grade; demote.See Synonyms at demote
降级：降低等级或衔位；降级参见 demote
To powder or pulverize.
磨成粉：捣碎或碾碎
To thin (paint) with a solvent.
稀释：用溶剂使（染料）变稀
To lower the price of:
降价：降低……的价格：
例句：
The store has drastically reduced winter coats.
商店对冬装大减价

To put in order or arrange systematically:
有系统地整理：按顺序或系统地安排或组织：
例句：
reduce a complex tax situation.
将复杂的税务系统化

To separate into orderly components by analysis.
分析：通过分析分离成有序的成份
Chemistry
【化学】
To decrease the valence of (an atom) by adding electrons.
降低原子价：通过加入电子来减少（原子的）电子价
To remove oxygen from (a compound).
去氧：把（化合物）中的氧分离出去
To add hydrogen to (a compound).
加氢：在（化合物）中加氢
To change to a metallic state by removing nonmetallic constituents; smelt.
冶炼，提炼：通过除去非金属成分而变成金属状态；熔炼
Mathematics To simplify the form of (an expression, such as a fraction) without changing the value.
【数学】 约分：在不改变值的情况下简化（表达式，如分数的）形式
Medicine To restore (a fractured or displaced body part) to a normal condition or position.
【医学】 使复原，使复位：使（身体骨折或脱臼的部分）恢复到正常的状态或位置
v.intr.（不及物动词）
To become diminished.
变少
To lose weight, as by dieting.
减轻体重：如通过节食来减轻体重
Biology To undergo meiosis.
【生物学】 减数分裂

来源：
Middle English reducen [to bring back]
中古英语 reducen [带回]
from Old French reducier
源自 古法语 reducier
from Latin redôcere
源自 拉丁语 redôcere
re- [re-]
re- [前缀，表.回应，后退.]
dôcere [to lead] * see deuk-
dôcere [引导] *参见 deuk-

【引伸】
reduc.er
n.（名词）
reduc.ibil.ity
n.（名词）
reduc.ible
adj.（形容词）
reduc.ibly
adv.（副词）