What is one who does not adopt extreme opinions in politics, or the like; one who fluctuates between parties, so as to appear to favor each; a timeserver. Thus Halifax was a trimmer on principle. Macaulay called?

trimmer — One who does not adopt extreme opinions in politics, or the like; one who fluctuates between parties, so as to appear to favor each; a timeserver. Thus Halifax was a trimmer on principle. Macaulay. (Webster's 1913.)