Jactitation

Jactitation is a word stemming from the Latin iactare, to throw.

Legal jactitation

In English law, jactitation is the maliciously boasting or giving out by one party that he or she is married to the other.

In such a case, in order to prevent the common repudiation of their marriage that might ensue, the procedure is by suit of jactitation of marriage, in which the petitioner alleges that the respondent boasts that he or she is married to the petitioner, and prays a declaration of nullity and a decree putting the respondent to perpetual silence thereafter. To the suit there are three defences: denial of the boasting;
the truth of the representations;
allegation (by way of estoppel) that the petitioner acquiesced in the boasting of the respondent.

In Thompson v. Rourke, 1893, Prob. 70, the Court of Appeal laid down that the court will not make a decree in a jactitation suit in favour of a petitioner who has at any time acquiesced in the assertion of the respondent that they were actually married.

Prior to 1857 such a proceeding took place only in the Ecclesiastical Court, but by express terms of the Matrimonial Causes Act 1857 it could be brought in the probate, divorce and admiralty division of the High Court. The right to petition for jactitation of marriage was abolished by Section 61 of the Family Law Act 1986.

In addition, this term may refer to acts such as slander of title or other similar misrepresentations of the ownership of physical or intellectual property.

Physical jactitation

Jactitation is an archaic medical term (derived, perhaps as a corruption, from "jactation", meaning a restless tossing and turning of the body, and derived itself from Latin jactare or jacere, both meaning "to throw or hurl") referring to the involuntary spasm of a limb, muscle, or muscle group. This is sometimes seen in fever patients or other situations of physical distress, but may occur in healthy individuals in a hypnogogic state. This hypnagogic jactitation often occurs in the legs, and may occasion a short explanatory dream about stumbling or missing the bottom stair.