Keylley \ke(yl)-ley\ as a girl's name is a variant of Keely (Gaelic), and the meaning of Keylley is "slender, pretty".
The baby name Keylley sounds like Kaylley, Keyley and Kelley. Other similar baby names are Kalley, Kayley, Nelley, Keyllie, Keylie, Keeley, Kealey, Kelbey, Kellen, Kelly, Kellee, Kelsey, Kellsey, Kelcey, Kyley, Keyely and Reilley.