Tilly-vally \Til"ly-val`ly\, interj., adv., or a.
A word of unknown origin and signification, formerly used as
expressive of contempt, or when anything said was rejected as
trifling or impertinent. [Written also {tille-vally},
{tilly-fally}, {tille-fally}, and otherwise.] --Shak.
[1913 Webster]