v (intransitive) To roll one's self about, as in mire; to tumble and roll about; to move lazily or heavily in any medium; to flounder; as, swine wallow in the mire.
v (intransitive) To immerse oneself in, to occupy oneself with, metaphorically.
v (intransitive) To roll; especially, to roll in anything defile|defiling or unclean, as a hog might do to dust its body to relieve the distress of insect biting or cool its body with mud.