Sip usually meaning : oke, fine, acceptable nice, great (probably from the English word “safe”).

There's no equivalent literal translation in Indonesian but it's an expression which can mean: alright, nice, great, well done, and anything to appraise one's condition or work.

Sip has the same meaning as OK/ Okay. "Sip" is like slang in Bahasa, if you use sip instead ok you'll sound like a native. You also can use "siap bos", "ncipp" and so many slang in Bahasa haha.

Hehe.. good question! Somebody has already answered it anyway. So, I just want to suggest you to use it more often, because it'll make sounds more natural.

Sip = Oke