The name Elissa is a girl's name of Hebrew, German origin. Elissa and discussed in our forums with posts like "Spelling Bee Name Game".
From the experts:
The Elissa version of a long-popular name is fading in favor of Alyssa, Eliza and other variants. The legion of other forms and spellings includes Alissa, Allissa, Allyssa, Alyssa, Elissah, Ellisa, Ellissa, Ellyssa, Elys, Elyssa, Elyssia, Ilissa, Ilysa, Ilyssa, Lissa, Lissie, Lissy Lyssa.