以下这些形容词都含有"完全地或不完全地缺少光亮" 的意思
dark：最普通用词，指缺乏自然光线或人工照明，使某物漆黑无光或光线十分微弱。
dim：指光线不足或视力较差，不能清晰地看见物体。
black：侧重颜色是黑色的，有时也指无光的黑暗。
gloomy：指光线不足或部分光线受阻而出现的阴暗。
obscure：指因光线不充足而使物体灰暗不清，失去光泽或若隐若现。作借喻时指因复杂、深奥或含糊而难于理解。
vague：通常作借喻用，形容抽象事物。
grey与dark意思相近，但侧重阴暗单调的意味。
以下这些形容词均包含 "不明确的，模糊的" 的意思
vague：多指因语言不确切，太笼统或因构思含糊、不完善而造成模糊难解。
dim：侧重指或因光线暗淡，或因年代久远、身体欠佳等因素而产生视觉或察觉方面的困难。
indefinite：指无明确定义或限定，重点或总体轮廓不明确。
obscure：语气最强，指晦涩难懂。
ambiguous：指文章或讲话中，意思可能有多种理解，令人捉摸不定。
faint：指对某事物印象不深，或指声音微弱或希望的渺茫等。

柯林斯高阶英汉双解学习词典释义

ADJ-GRADED

无名的；鲜为人知的；默默无闻的

If something or someone is obscure, they are unknown, or are known by only a few people.
例句
The origin of the custom is obscure... 这一习俗的起源鲜为人知。 The hymn was written by an obscure Greek composer for the 1896 Athens Olympics. 这首赞歌是希腊一位名不见经传的作曲家为1896年的雅典奥运会创作的。
ADJ-GRADED

（通常指因内容繁琐）晦涩的，费解的，难懂的

Something that is obscure is difficult to understand or deal with, usually because it involves so many parts or details.
例句
The contracts are written in obscure language... 这些合同的语言晦涩难懂。 Richard's statement was disgracefully obscure. 理查德的声明隐晦费解，真是丢人。
VERB

遮掩；遮蔽；使模糊不清

If one thing obscures another, it prevents it from being seen or heard properly.
例句
Trees obscured his vision; he couldn't see much of the Square's southern half... 树木遮挡了他的视线，南半广场的一大部分他都无法看清。 One wall of the parliament building is now almost completely obscured by a huge banner. 议会大楼的一面墙现在几乎被一条巨型横幅完全盖住了。
VERB

使晦涩；使费解；使难懂

To obscure something means to make it difficult to understand.
例句
...the jargon that frequently obscures educational writing... 经常让普教著作变得艰深晦涩的术语 This issue has been obscured by recent events. 最近发生的一些事件使这一问题变得混淆不清。

英汉词典释义

adj.
不出名的，无名的，鲜为人知的; 不重要的
There are many minor and obscure poets in the age of Elizabeth. 伊丽莎白时代有许多不知名的诗人。
费解的，难以理解的; 模糊不清的
The point of his speech is obscure. 他发言的要点模糊不清。
不易看清的, 暗淡的
The room is too obscure for reading. 这房间太昏暗了, 无法看书。
vt.
使…模糊不清，使隐晦，使费解; 掩盖
Her poor English obscured her meaning. 她的英语差, 难以表达自己的意思。 My view was obscured by the trees. 我的视线被树挡住了。

英英词典释义

Verb
1. make less visible or unclear;
"The stars are obscured by the clouds"
2. make unclear, indistinct, or blurred;
"Her remarks confused the debate""Their words obnubilate their intentions"
3. make obscure or unclear;
"The distinction was obscured"
4. make undecipherable or imperceptible by obscuring or concealing;
"a hidden message""a veiled threat"
5. make difficult to perceive by sight;
"The foliage of the huge tree obscures the view of the lake"
Adjective
1. not clearly understood or expressed;
"an obscure turn of phrase""an impulse to go off and fight certain obscure battles of his own spirit"-Anatole Broyard"their descriptions of human behavior become vague, dull, and unclear"- P.A.Sorokin"vague...forms of speech...have so long passed for mysteries of science"- John Locke
2. marked by difficulty of style or expression;
"much that was dark is now quite clear to me""those who do not appreciate Kafka's work say his style is obscure"
3. difficult to find;
"hidden valleys""a hidden cave""an obscure retreat"
4. not famous or acclaimed;
"an obscure family""unsung heroes of the war"
5. not drawing attention;
"an unnoticeable cigarette burn on the carpet""an obscure flaw"
6. remote and separate physically or socially;
"existed over the centuries as a world apart""preserved because they inhabited a place apart"- W.H.Hudson"tiny isolated villages remote from centers of civilization""an obscure village"