Well, there's no specific "meaning" per se (it's not like I'm into the dam or the early 20th century American president or the vacuum cleaner, and I'm not a coke fiend or an oral sex fie--- wait, scratch that, I am an oral sex fiend but that's not why I'm called "Hoover"), but Hoover has been my nickname/stage name/alter ego for almost 3 decades.
It all started in the early 80s when I was working on a recording project with a band called Any Two Words. In addition to being the band's bass player and one of their composers, I was also engineering the album...and when they did the first mock-up of the liner notes, frankly I just got embarassed seeing my name credited so many times. So I arbitrarily came up with the name "Hoover Rezillo" and asked that the engineering be credited to him.
Fast-forward a few years: I had just moved to New York City where I was simultaneously pursuing freelance work as a bass player and an audio engineer. To keep all the hundreds of job offer phonecalls that were pouring in (that's a joke, kids) straight in my mind, I had given my real name to all the audio contacts and "Hoover" to all the bass playing contacts. Basically lived a double life for a while. Had to get my checking account info modified so I could deposit paychecks made out to "Hoover". Strangely, the IRS didn't give a hoot.
In the late 80's I wound up getting a gig on a European musical theater bus&truck tour through one of the musicians I'd met early in my NYC residence, so since he knew me as Hoover the employer & cast & crew knew me as Hoover also. And since I met my wife on that tour, she was introduced to me as Hoover and has called me that ever since. Her whole family calls me Hoover. All of her friends call me Hoover. And they all have for over 20 years.
And they still ask "What does 'Hoover' mean?" and I still don't have a good answer.