twankay, n. — Green’s Dictionary of Slang

twankay n.

also twankey

[tea trade jargon twankey, green tea, thus ? the root of the pantomime dame Widow Twankey]

gin.

1900		F. Adams in N&Q Ser. 9 VI 163/1: A friend mentions ‘twankay’, properly denoting a kind of green tea, as a name by which gin is frequently called .
1937–84		Partridge DSUE (1984) 1276: [...] from late 1890s.