"thick, clotted blood," Old English gor "dirt, dung, filth, shit," a Germanic word (cognates: Middle Dutch goor "filth, mud;" Old Norse gor "cud;" Old High German gor "animal dung"), of uncertain origin. Sense of "clotted blood" (especially shed in battle) developed by 1560s (gore-blood is from 1550s).
"triangular piece of ground," Old English gara "corner, point of land, cape, promontory," from Proto-Germanic *gaizon- (source also of Old Frisian gare "a gore of cloth; a garment," Dutch geer, German gehre "a wedge, a gore"), from PIE *ghaiso- "a stick, spear" (see gar). The connecting sense is "triangularity." Hence also the senses "front of a skirt" (mid-13c.), and "triangular piece of cloth" (early 14c.). In New England, the word applied to a strip of land left out of any property by an error when tracts are surveyed (1640s).