blue ribbon, n. — Green’s Dictionary of Slang

blue ribbon n.

[SE blue ribbon, a blue ribbon worn as a badge of honour; thus referring to the quality of the best gin]

gin.

1811		Lex. Balatronicum n.p.: Blue ribbin. Gin. The cull lushes the blue ribbin; the silly fellow drinks common gin.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.
1833		‘The Knight of the New Iron Goose’ in Rummy Cove’s Delight in Spedding & Watt (eds) Bawdy Songbooks (2011) III 99: The ribbon blue her drunk Knight flash’d .