Green’s Dictionary of Slang

an inhabitant of Yarmouth.

1846		Swell’s Night Guide 58: I takes my pitch last night on Fleet pave, then meets with Bet Flab, the Yarmouth bloater.
1849		Dickens David Copperfield (1991) 29: Peggotty said [...] that [...] she was proud to call herself a Yarmouth Bloater.