Do you know ghouls from goblins and ghosts?
1570s, "to look at furtively," from a Scandinavian source, cf. Old Norse glotta "to grin, smile scornfully, show the teeth," Swedish dialectal glotta "to peep;" or from Middle High German glotzen "to stare, gape." Sense of "to look at with malicious satisfaction" first recorded 1748. Related: Gloated; gloating. As a noun, from 1640s with sense of "side-glance;" 1899 as "act of gloating."