a. - To become, or be, rank; to grow rank or strong; to be inflamed; to fester; -- used literally and figuratively.
a. - To produce a festering or inflamed effect; to cause a sore; -- used literally and figuratively; as, a splinter rankles in the flesh; the words rankled in his bosom.
v. t. - To cause to fester; to make sore; to inflame.