constitution (n.) Look up constitution at Dictionary.com
mid-14c., "law, regulation, edict," from Old French constitucion (12c.) "constitution, establishment," and directly from Latin constitutionem (nominative constitutio) "act of settling, settled condition, anything arranged or settled upon, regulation, order, ordinance," from constitut-, past participle 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.