votary \VOH-tuh-ree\ (noun) - 1. One who is devoted, given, or addicted to some particular pursuit, subject, study, or way of life. 2 : A devoted admirer. 3 : A devout adherent of a religion or cult. 4 : A dedicated believer or advocate.
"A priestess led a young man out onto the sunken floor, pulling him with a chain fixed to the manacles on his wrists; a second votary walked behind him, a sword at his back." -- Mark E. Rogers, 'Blood + Pearls'
Votary comes from Latin votum, "vow," from the past participle of vovere, "to vow, to devote." Related words include vow and vote, originally a vow, hence a prayer or ardent wish, hence an expression of preference, as for a candidate.