Definitions for unboundʌnˈbaʊnd
Random House Webster's College Dictionary
Ref: pt. and pp. of unbind .
(adj.)not bound, as a book.
free; not attached.
Origin of unbound:
not secured within a cover
"an unbound book"
not restrained or tied down by bonds
not held in chemical or physical combination
imp. & p. p. of Unbind