flatterin, flatrin, flattrin noun a fish, sometimes specifically a herring: God curse you fish, I’ve burned my hand wi you, you adulterated flattrin 19-. etymology: origin obscure; but seems to be only in Scots Travellers’ usage; attested by Galloway and Perthshire and Argyleshire Tinkler-Gypsies, BS in TDITA, JS and SS; also collected by EMcC/PS, RD and Rev John Baird from Kirk Yetholm Gypsies note:

Cited in the form flatrin ‘fish’ from Canadian Paul Pope (2013).