the bilge is the part of a ship below the floor boards of the bottom level, just above the hull... ie the darkest and most grim part of the boat. a rat is, well, a small annoying (and to some people, scary) rodent. Therefore the term "bilge rat" is a pirate insult.
by Mad Sam purple'ead January 4, 2005
A Stoker or Spanner Wanker in the Royal Navy. Officially, they are Marine Engineering Mechanics or MEMs. Also, it's accurate since they usually spend a lot of time in the underbelly of a ship.
by Mr Rusher August 17, 2007
Someone who doesn’t own a boat or has no intention of ever owning a boat but enjoys fishing and will do anything to go out in his friends or acquaintance’s boats.
by Barracod May 20, 2019