apart

形容词 apart:

1. remote and separate physically or socially
   同义词：isolated, obscure
2. not living together as man and wife
   同义词：separate, separated
3. having characteristics not shared by others- Vannever Bush

副词 apart:

1. separated or at a distance in place or position or time
2. not taken into account or excluded from consideration
   同义词：aside
3. away from another or others
4. placed or kept separate and distinct as for a purpose
   同义词：aside
5. one from the other
6. into parts or pieces
   同义词：asunder

1. He took my essay apart but I found his criticism helpful.
   他把我的文章狠狠地批评了一顿，但我认为他的批评有好处
2. The two villages are three miles apart.
   这两个村子相距三英里。
3. He took the watch apart to repair it.
   他把手表拆开来修理。
4. I can't tell the twins apart.
   我辨认不出这对双胞胎。

a.part

adv.（副词）

At a distance in place, position, or time:
相隔，相距：在地点，方位或时间上成距离：
例句：
railings spaced two feet apart; born three years apart.
栏杆之间相距两英尺；出生相隔三年

Away from another or others:
分散地，分开地：与另一个或其它的分开：
例句：
grew apart over the years; decided to live apart.
几年来独自成长；决定离群索居

In or into parts or pieces:
成部分，成碎片：
例句：
split apart.
裂成碎片

One from another:
分辨：与另一个区别开：
例句：
I can`t tell the twins apart.
我无法区分这一对双胞胎

Aside or in reserve, as for a separate use or purpose:
搁置，保留：为另一用途或目的分开或保留：
例句：
funds set apart for the project.
为这项工程拨出的资金

As a distinct item or entity:
有区别地：不同的项目或实体：
例句：
Quality sets it apart.
质量使其与众不同

So as to except or exclude from consideration; aside:
撇开，排除在外；在一旁：
例句：
All joking apart, I think you`re crazy.
撇开玩笑不谈，我认为你是发疯了

adj.（形容词）
Set apart; isolated. Used after a noun or in the predicate:
分离的；隔离的：分离的；隔离的。用于名词后或谓语中：
例句：
a people who have existed over the centuries as a world apart.
作为与世隔绝的民族已经存在了几个世纪了

来源：
Middle English
中古英语
from Old French a part
源自 古法语 a part
a [to] from Latin ad- * see ad-
a [向，去] 源自 拉丁语 ad- *参见 ad-
part [side] from Latin pars part- * see part
part [边] 源自 拉丁语 pars part- *参见 part

【引伸】
apart.ness
n.（名词）