Definition of "ratty"

Resembling or characteristic of a rat; ratlike.  examples

Infested with rats.  examples

(figuratively, informal)

1. In poor condition or repair.  quotations  examples

   Quotations

   • We got an old tin lantern, and a butcher knife without any handle, and a bran-new Barlow knife worth two bits in any store, and a lot of tallow candles, and a tin candlestick, and a gourd, and a tin cup, and a ratty old bed-quilt off the bed, […] and just as we were leaving I found a tolerable good curry-comb, and Jim he found a ratty old fiddle-bow, and a wooden leg.

     1884 December 10, Mark Twain [pseudonym; Samuel Langhorne Clemens], chapter IX, in The Adventures of Huckleberry Finn: (Tom Sawyer’s Comrade) […], London: Chatto & Windus, […], page 78

   • The Marcher lord was still clad in his ratty black cloak and dented breastplate with its chipped enamel lightning.

     2000, George R.R. Martin, A Storm of Swords, Bantam, published 2011, page 535

   • I was having exactly that thought on a ratty mock-leather couch in Islington.

     2006, Clive James, North Face of Soho, Picador, published 2007, page 80

2. (Australia) Crazy, mad; ridiculous; slightly strange, eccentric; also (followed by about, on, or over), attracted to, infatuated with.  examples

3. (originally British) Annoyed, bad-tempered, irritable.  quotations  examples

   Quotations

   • He got bad, he got ratty, he would take it out on people around him. He was mean when it turned against him.

     2009, Ian McDonald, River of Gods

Synonym of knock down ginger (“prank of knocking on a front door and running away”)  examples