Here's a little summary of our affair with the French:
French kiss - various sexual connotations and its synonymy is thought to date back to the height of Anglo-French enmity in 1730-1820.
French lessons - translating as services offered by a prostitute
Menage a trois - a domestic arrangement in which three people having sexual relations occupy the same house
French Prints - signifying pornographic prints
Frenchified - having syphilis
French Letter - an euphemism for a condom, which in turn the French call 'Copote Anglaise'.
Mind My French - pardoning blue language
You see, we English have much to thank the French for!
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