Smart
Part of speech: adjective
Definition: Exhibiting social ability or cleverness. Exhibiting intellectual knowledge, such as that found in books. Good-looking. Cleverly and/or sarcastically humorous in a way that may be rude and disrespectful. Cf: (verb) to smart off; (noun) smarty pants, wise guy, wiseacre, wise-ass; (adjective) cute. Sudden and intense. Intense in feeling; painful. Used usually with the adverb intensifier right.
Part of speech: verb
Definition: To hurt or sting.
Example sentence: The thing about hip-hop today is it's smart, it's insightful. The way they can communicate a complex message in a very short space is remarkable.
Shrewd
Part of speech: adjective
Definition: showing clever resourcefulness in practical mattersartful, tricky or cunningstreetwise
Example sentence: What I'm saying is that there are bargains right now, there are stocks right now that if you're shrewd enough, you will be able to buy them at the opening today and I you'll make money in a year from now.