done or made using whatever is available; "crossed the river on improvised bridges"; "the survivors used jury-rigged fishing gear"; "the rock served as a makeshift hammer"
casually thoughtless or inconsiderate; "an offhand manner"; "she treated most men with offhand contempt"
in a casually inconsiderate manner; "replied offhand, his mind a million miles away"; "she threw him over offhandedly without even a Dear-John letter"
without previous thought or preparation; "couldn't give the figures offhand"; "we decided offhand to go to Canada"; "she had made these remarks offhandedly"