Yes - cockney slang for "a male person" - hence I'm a Geezer geezer in my earlier post.

Also, it was the trade name (which became generic) for a gas-powered water-heater, popular over here in the 50s and 60s. A cognate name, of course, but different from a natural hot spring, nevertheless.

And, in all three cases, pronounced GEY-ser (to rhyme with KEY-)