I drilled into some of the links in that article, but nowhere did I find a definition of "underemployed" in this context. Is there a standard definition? Or di

I drilled into some of the links in that article, but nowhere did I find a definition of "underemployed" in this context. Is there a standard definition? Or did I just miss the definition in the article? "Jobs that don't require a degree" is a very squishy definition, if that's what was used. Technically, software development doesn't require a degree - I work with several excellent developers who lack credentials.