Why "razor" ?

I learned about Occam’s Razor a long time ago. But while cruising the Wikipedia I came across Hanlon’s Razor .

What I’m wondering though regards the use of the use of the word “razor”. How did it become to mean the same thing as “saying” or “adage”?

I don’t think it means “adage.” According to the Wikipedia page you linked to, Hanlon’s Razor might have been named for Occam’s Razor – and Occam’s Razor is, I think, named that because it is a rule for shaving away irrelevance and confusion.

It didn’t, and doesn’t, mean “saying” or “adage.” While Occam’s Razor can be presented as an adage, the term “razor” applies to the concept. It figuratively cuts the crap away from the truth, as BrainGlutton suggests.