WordNet sense 1 (a small glass adequate to hold a single swallow of whiskey):

pony, shot glass

WordNet sense 2 (any small mast on a sailing vessel; especially the mizzenmast of a yawl):

jiggermast

WordNet sense 3 (larval mite that sucks the blood of vertebrates including human beings causing intense irritation):

chigger, redbug, harvest mite