discreet

discreet, discrete

这是两个形近单词。
discreet: 意思是“（言行）谨慎的”、“慎重的”“有判断力的”（not saying too much；showing good sense and judgment），它的名词是 discretion.反义词是鲁莽: indiscreet（形容词）及 indiscretion （名词）。

• the action he takes is far from discreet.
  他所采取的行动很不谨慎。
• you must show more discretion in choosing your friends.
  你在选择朋友时要谨慎些。

discrete: 意思是“分离的”、“不联络的”、“各异的”（separate，disjoined or individually distinct）。它的名词是 discreteness.

• this proposition contains two discrete parts.
  这个建议由两个不同的部分组成。
• our company is made up of many samll，discrete units.
  我们的公司由许多小的各自分立的单位组成。

形容词 discreet:

1. marked by prudence or modesty and wise self-restraint
2. unobtrusively perceptive and sympathetic
   同义词：discerning
3. heedful of potential consequences
   同义词：circumspect

1. Be more discreet or you'll get yourself talked about.
   要更谨慎些－－否则你就会成为人们的话柄。
2. I'll certainly be most discreet in my conversation.
   我在谈话中当然会十分小心的。
3. It was not discreet of you to say that.
   你那样说有欠考虑。

dis.creet

adj.（形容词）
Marked by, exercising, or showing prudence and wise self-restraint in speech and behavior; circumspect.
谨慎的，慎重的：以谨慎和理智的自我控制为特征的，做事谨慎理智的，或在言行上表现出谨慎和理智的自我控制；周到的
Free from ostentation or pretension; modest.
朴素的，谦逊的；端庄的

来源：
Middle English
中古英语
from Old French discret
源自 古法语 discret
from Medieval Latin discrôtus
源自 中世纪拉丁语 discrôtus
from Latin [past participle of] discernere [separate, to discern] * see discern
源自 拉丁语 [] discernere的过去分词 [分离；辨别，觉察] *参见 discern

【引伸】
discreet.ly
adv.（副词）
discreet.ness
n.（名词）