ˈɹiːzən the quality of being plausible or acceptable to a reasonable person he questioned the tenability of my claims moderation in expectations without greater reasonableness by both parties we will never settle this matter! the property of being moderate in price or expenditures the store is famous for the reasonableness of its prices the modestness of the living standards here becomes obvious immediately goodness of reason and judgment the judiciary is built on the reasonableness of judges the state of having good sense and sound judgment his rationality may have been impaired he had to rely less on reason than on rousing their emotions