Here's a word I've just learned this year-"suss".

I believe that "suss" comes from Jamaica or some other Caribbean nation, but I'm not sure about that. Maybe it's just used quite a lot in Jamaica or some other Caribbean nature but it comes from old English or some other language. ??

suss (sŭs)

tr.v. Slang., sussed, suss·ing, suss·es.
To infer or discover; figure out: "I think I'm good at sussing out what's going on" (Ry Cooder).

To size up; study: "Suss out the designers in whom you are interested" (Lucia van der Post).

http://www.answers.com/topic/suss

-snip-

Here's a sentence I've made up with that word-all by myself!

I love sussin out the origins & meanings of words & phrases.