Green’s Dictionary of Slang

nonsense! rubbish!

1862		Thackeray Adventures of Philip (1899) 370: Rot, indeed!
1885		Bulletin (Sydney) 2 May 10/1: O Rot, ambrosial Rot, fain would I wing / My way up to thy Himaleh, and sing / With thee, the Tenth Muse, of this age begot – / An age of promise, now all gone to pot.
1890		Sporting Times 15 Feb. 1/2: ‘I shall get five years.’ ‘Rot!’.
1897		Kipling ‘Slaves of the Lamp — Part I’ in Complete Stalky & Co. (1987) 61: ‘Rot!’ said M’Turk. ‘The Head never expels except for beastliness or stealing.’.
1905		Sporting Times 4 Feb. 1/4: A pony for the loan of a measly hundred, for thirty days — oh, rot!
1913		A. Lunn Harrovians 31: ‘Where’s your father now?’ ‘I don’t know.’ ‘Rot! you must know.’.
1928		R. Hall Well of Loneliness (1976) 216: ‘You look tired to death; why not lie down and rest?’ ‘Rot! I want to work.’.
1939		V. Davis Gentlemen of the Broad Arrows 212: Rot! The doctors are not like that.
1944		A. Marshall These Are My People (1957) 156: ‘It was a good lamb,’ said Sam humbly. ‘Rot!’ said Mick. ‘You haven’t got no good lambs.’.
1961		‘Frank Richards’ Billy Bunter at Butlins 120: ‘Rot!’ said Bunter.
1968		P. Barnes Ruling Class I iv: Love? Tucker? Rot.
1981		A. Weller Day of the Dog 28: ‘What rot,’ she cries, for that life is behind her now.