Saying that this is "an idiomatic meaning of Soj", is the same as saying "it is a slang meaning" ?
Is there a difference between an idiomatic use of a word and a slang word ?
Slang is slang for “idiom” (just kidding).
While both idiom and slang may use existing words to mean things other than their literal meanings, use of slang is generally restricted to a particular region and/or subculture, while idiom tends to be more generally used. Slang may also use newly invented words, while idiom must use words that already have a non-idiomatic meaning.