The Collaborative International Dictionary
De jure \De` ju"re\ [L.] By right; of right; by law; -- often opposed to de facto.
Douglas Harper's Etymology Dictionary
Latin, literally "of law," thus "legitimate, lawful, by right of law, required by law." Jure is ablative of ius (see just (adj.)).
Wiktionary
a. By right, in accordance with the law, legally.
WordNet
adj. by right; according to law; "de jure recognition of the new government" [ant: de facto]
adv. by law; conforming to the law; "we are lawfully wedded now" [syn: legally, lawfully, wrongfully] [ant: unlawfully]
Wikipedia
de jure (adjective, adverb) (, ; Classical Latin: de iure ; lit. 'from law') means 'a state of affairs that is in accordance with law', i.e. that is officially sanctioned. In contrast, de facto (lit. 'from fact'), means 'a state of affairs that is true in fact, but that is not officially sanctioned'. In law, and in government, the terms de jure and de facto are used instead of 'in law' and 'in practice', respectively. In a legal context, de jure (laws) are contrasted to de facto practices, where, for example, the people obey a contract as though there were a law enforcing it, yet there is no such law. A process known as ' desuetude' may allow (de facto) practices to replace (de jure) laws that have fallen out of favour locally.