Noun
a warrant formerly issued by a French king who could warrant imprisonment or death in a signed letter under his seal
Source: WordNetLettre de cachet to avoid scandal to touch high-placed accomplices). Source: Internet
Victims of Lettre de cachet * Charles Simon Favart (because a nobleman was interested in his wife) * Luke Joseph Hooke (deprived of his academic chair in theology for awarding a Ph. Source: Internet