The Collaborative International Dictionary of English v.0.48:

De jure \De` ju"re\ [L.]
   By right; of right; by law; -- often opposed to de facto.
   [1913 Webster]

WordNet (r) 3.0 (2006):

de jure
    adv 1: by law; conforming to the law; "we are lawfully wedded
           now" [syn: legally, lawfully, de jure] [ant:
           unlawfully]
    adj 1: by right; according to law; "de jure recognition of the
           new government" [ant: de facto]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

DE JURE, by right. Vide De facto.