Source : Webster's Revised Unabridged Dictionary (1913)

Worshiper \Wor"ship*er\, n.
   One who worships; one who pays divine honors to any being or
   thing; one who adores. [Written also {worshipper}.]

Source : WordNet®

worshiper
     n 1: someone who admires too much to recognize faults [syn: {worshipper}]
     2: a person who has religious faith [syn: {believer}, {worshipper}]