A vulgar reference to an:
idiot,
moron, jerk. Used to convey the mental image of a
man metaphorically described as a wadded-up ball of a tallywhacker (otherwise known as a penis).
Good sir! You have just applied your forefoot to the
top of my heel and unearthed my foot from its leather placing! I inquire an apology,
post-haste,
dickwad!