Green’s Dictionary of Slang

1. a native of Kent.

1654

Mercurius Fumigosus 26 22-30 Nov. 7: An Essex Calf [...] chansed not long since to tumble down the hill among the languine Dragonians at Temple-Barr, who being accompanied with a Kentish Long-taile [...] brought with them an Innocent Lamb, whom they had prepared for the slaughter, intending to cut his throat with a ten-shillings Knife.

2. a rat.

1901

F. Swainson Acton’s Feud [ebook] ‘Is there a record then for rat killing? How is it done?’ ‘Turn a sack o' long tails on to the floor and let the dawg among them. He works against time’.