constituo

Constituo, constituere, constitui, constitutum, third conjugation: cum plus statuo, "set up together". The stem vowel of statuo weakens to i in the compound, which is why it is constituo and not constatuo.

Three uses worth separating. With a thing as object it founds or establishes: urbem constituere. With a person as object it appoints or stations, which is where English "constitute" misleads - constituere aliquem regem is to make someone king, not to compose him. With an infinitive or an ut-clause it means "decide", and that is the commonest sense in prose. Note also that constituit is both present and perfect third singular, distinguished only by the length of the i, which the site writes without macrons; context decides. The neuter participle constitutum became a noun meaning "an appointment, an agreed arrangement", and gives English constitution and constituent.