words in English that contradict themselves

[S1E10, TBBT]
Leonard: I don't get it. I already told her a lie. Why would I replace it with a different lie?
Sheldon: Well, first of all, your lie was laughably transparent (clear and easy to understand), whereas (but in contrast) mine is exquisitely (extremely beautiful and very delicately made) convoluted (complicated). While you were sleeping, I was weaving an un-unravelable web.

ravel有两个相反的意思：1) （使线）缠结; 2) （使织物）散线, 绽线。unravel取了第一个意思，又加上了比喻，as in "unravel the mystery" (如果认为un-表示否定；解开谜团)。

undisclosed和undiscovered与之有点类似，也有双重否定，但用了un-和dis-。

[cudoo稻糠亩]，还有dust, sanction等例子。如除尘和布尘都是dust. 还有The ship was held fast (firmly, securely, tightly ) by the anchor chain.

在古英语里，fast是"firmly fixed, steadfast, constant; secure; enclosed, watertight; strong, fortified," probably from Proto-Germanic *fastu- "firm, fast" (source also of Old Frisian fest, Old Norse fastr, Dutch vast, German fest)，应该和fasten是近亲。Meaning "rapid, quick" is from 1550s (明嘉靖30年) [etymonline稻糠亩]

还有ravish【牛津】:
ravish
1. [Tn esp passive 尤用於被动语态] fill (sb) with delight; enchant 使（某人）欣喜若狂; 使着迷; 使心醉
2. [Tn] (arch or fml 古或文) rape (a woman or girl)

If an animal or bird preys on another animal or bird, it hunts and eats it. prey - an animal, bird etc that is hunted and eaten by another animal. prey和predator不如preyer和preyee好啊。

知道lava和magma两个单词，就敢说英语比汉语高级？加起来才9个字母，5个不重复的(aglmv)。