Lonnie \l(on)-nie\ as a girl's name (also used as boy's name Lonnie), is a variant of Loni. See for origin and meaning of Lonnie.
The baby name Lonnie sounds like Lannie, Lonni, Lonie and Linnie. Other similar baby names are Bonnie, Connie, Donnie, Nonnie, Jonnie, Ronnie, Sonnie and Vonnie.