Trea"son*a*ble (?), a.
Pertaining to treason; consisting of treason; involving the crime of treason, or partaking of its guilt.
Most men's heads had been intoxicated with imaginations of plots and treasonable practices.
Syn. -- Treacherous; traitorous; perfidious; insidious.
--Trea"son*a*ble*ness, n. -- Trea"son*a*bly, adv.
© Webster 1913.