underside \ˈ ̷ ̷ ̷ ̷ˌ ̷ ̷, ˌ ̷ ̷ ̷ ̷ˈ ̷ ̷\noun Etymology:under (III) + side 1.: the side or surface lying underneath < underside of a leaf > 2.: the side usually hidden from sight : the worse side < with the underside of civilization revealing itself in slum and brothel — R.M.Kain >