The term “Constitution” came from Vattel.
Which would prove nothing, were it true, but it isn't. From the online etymology dictionary
mid-14c., "law, regulation, edict," from O.Fr. constitucion (12c.) "constitution, establishment," and directly from L. constitutionem (nom. constitutio) "act of settling, settled condition, anything arranged or settled upon, regulation, order, ordinance," from constitut-, pp. stem of constituere (see constitute). Meaning "action of establishing" is from 1580s; that of "way in which a thing is constituted" is from c.1600; that of "physical health, strength and vigor of the body" is from 1550s; of the mind, "temperament, character" from 1580s. Sense of "mode of organization of a state" is from c.1600; that of "system of principles by which a community is governed" dates from 1730s; especially of a document of written laws since the U.S. and French constitutions, late 18c.The Oxford English Dictionary traces it back even further, mentioning the Constitution of Clarendon from 1164. So, no, it was used before Vattel.