":while they may or may not have created the term out of whole cloth, it seems pretty obvious to me (a yank) that it is a reference to PENIS.  ""to hose someone"" means to screw someone, either in the sexual sense or the defraud sense.  hoser is just an extension of this.  basically a softer version of ""fucker"", ""prick"" or ""dick""  maybe closer to ""wienie"" or ""dink""? 

 :the other etymologies about gas stations and ice-rinks sound ridiculous.  adolescent frat-boy slang with clear sexual overtones  why look elsewhere?!    

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