Having distinctive piquancy, as racy wine. It was first applied to wine, and, according to Cowley, comes to us from the Spanish and Portuguese raiz (root), meaning having a radical or distinct flavour; but probably it is a corruption of “relishy” (French, reléché, flavourous).
Rich, racy verse, in which we see The soil from which they come, taste, smell, and see
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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