The term 'unwaveringly loyal' can be summed up in one word: trueblue. Trueblue is an adjective that describes someone who is unwaveringly loyal and devoted to a cause, person, or group. It is often used to describe someone who is a faithful supporter of a particular team, organization, or political party. Trueblue is also used to describe someone who is steadfastly committed to a set of beliefs or principles.