(i.e. Bridget). A generic name for an Irish servant-maid, as Mike is for an Irish labourer. These generic names are very common: for example, Tom Tug, a waterman; Jack Pudding, a buffoon; Cousin Jonathan, an American of the United States; Cousin Michel, a German; John Bull, an Englishman; Moll and Betty, English female servants of the lower order; John Chinaman, a Chinese; Colin Tompon, a Swiss; Nic Frog, a Dutchman; Mossoo, a Frenchman: and many others.
In Arbuthnot's John Bull Nic Frog is certainly a Dutchman; and Frogs are called “Dutch Nightingales.” The French sometimes serve Liège frogs at table as a great delicacy, and this has caused the word to be transferred to the French; but, properly, Nic Frog is a Dutchman.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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