Are you sure about the meaning though? Afaik, it started to be used in the context of UX/UI starting from the book "Atomic Design". That is also the earliest reference in the Wikipedia article.

Of course, there were systems in graphic design used earlier [1], but before 2016, the thing in the OP would be called "The US Web Design Patterns" or "...Language" or "...Toolkit" or "...Library", for the lack of a common term.

[1] http://assets.runemadsen.com/classes/programming-design-syst...