Joellyn \jo(e)-ll-yn\ as a girl's name is a variant of Joelle (French), and the meaning of Joellyn is "Jehovah is God".
The baby name Joellyn sounds like Joellin and Joellen. Other similar baby names are Joelly, Jaelyn, Jeslyn, Jolyn, Jocelyn, Jozlyn, Josslyn, Joslyn, Josilyn, Joselyn, Josalyn, Joclyn, Joelynn, Joely, Joella, Joell, Joelin, Jonalyn, Joeleen and Kellyn.