(1):
(n.) The missionary who first plants the Christian faith in any part of the world; also, one who initiates any great moral reform, or first advocates any important belief; one who has extraordinary success as a missionary or reformer; as, Dionysius of Corinth is called the apostle of France, John Eliot the apostle to the Indians, Theobald Mathew the apostle of temperance.
(2):
(n.) Literally: One sent forth; a messenger. Specifically: One of the twelve disciples of Christ, specially chosen as his companions and witnesses, and sent forth to preach the gospel.
(3):
(n.) A brief letter dimissory sent by a court appealed from to the superior court, stating the case, etc.; a paper sent up on appeals in the admiralty courts.