if you mean like rash behavior, its usually negative because it means you jump right into something without thinking. most of the time that's not a good thing.
Rash (as in, a rash decision. Or you could use risky)
If you mean the word "rash," typically the word has a negative connotation. When some acts "rashly," it means they are being reckless, careless, or perhaps over-the-top. That's the adjectival or adverbial (descriptive) use. For more evidence of this, simply look at the noun: rash - which is an irritation of the skin. That's bad. Apply a bad noun to an adjective and, typically, you get a word with a negative connotation.
A negative word.
is energetic a positive or negative word
No is negative yes is positive
mostly positive but you can use it in negative ways.
is stringy a positive or negative word
Negative
Browbeat is a negative word.
Negative: Accuse Positive: Justify
the word large is positive
It is a positive word