I was shocked to see there is no entry of "slangish" in dictionaries just a moment ago. I checked dozens of dictionaries, but none doesn't list it. Does that mean I should regard it as sub-standard? I've seen and heard it often used, and you get a lot of results returned on Google (but then again I know it doesn't necessarily mean it is an idiomatic word; there may be a lot of websites rendered by non-natives included). The word is straightforward, so maybe it is used as a coined word?
Hiro
Hiro