frugal + hep

Adj. slang. Variant of hip.

1. hep - informed about the latest trends, "aware, up-to-date."
First recorded 1908 in Saturday Evening Post, but said to be underworld slang, of unknown origin.
Taken up by jazz musicians by 1915; hepcat "addict of swing music" is from 1938. Later evolved into or was replaced by "hip".