Green’s Dictionary of Slang

1. a pheasant [SE].

1796		Grose Classical Dict. of the Vulgar Tongue (3rd edn).
1811		Lex. Balatronicum.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.

2. a school-master [swish v.¹ (1) + tail n. (1)].

1837		Thackeray Ravenswing (1887) 94: He was [...] placed under the care of the Rev. Mr. Swishtail, at Turnham Green.
1839		Comic Almanack Mar. 169: Papa [...] declared that I should not be removed from the school; and sent old Swishtail a brace of pheasants.
1889		Ipswich Jrnl 15 Feb. 5/2: The young squire still receives his instruction into the arts and sciences at the hands of Dr Swishtail.
1890–1904		Farmer & Henley Sl. and Its Analogues.

3. a horse with an undocked tail [SE].

1890–1904

Farmer & Henley Sl. and Its Analogues.