Gum
Middle English: from Old French gomme, based on Latin gummi, from Greek kommi, from Egyptian kemai .
wiktionary
From Middle English gome, from Old English gōma(“palate”), from Proto-Germanic *gōmô, *gaumô(“palate”) (compare German Gaumen, Old Norse gómr (whence Icelandic gómur)), from Proto-Indo-European *ǵʰh₂u-mo- (compare Tocharian A ko, Tocharian B koyṃ(“mouth”), Lithuanian gomurỹs(“palate”)), from Proto-Indo-European *ǵʰeh₂w-(“to gape, yawn”). More at yawn.
From Middle English gomme, gumme, borrowed from Anglo-Norman gome, from Late Latin gumma, from Latin cummi, gummi, from Ancient Greek κόμμι(kómmi), from Egyptian qmy(“anointing oil”), qmyt(“acanthus resin, gum”). Cognate with Spanish goma(“rubber”).
etymonline
gum (n.1)
c. 1300, "resin from dried sap of plants," from Old French gome "(medicinal) gum, resin," from Late Latin gumma, from Latin gummi, from Greek kommi "gum," from Egyptian kemai. As the name of a hardened, sweetened gelatine mixture as a candy, 1827. As a shortened form of chewing gum, first attested 1842 in American English. The gum tree (1670s) was so called for the resin it exudes. Latin gummi also is the source of German Gummi (13c.).
gum (n.2)
"soft tissues of the mouth," Old English goma "palate, side of the mouth" (single or plural), from a Germanic source represented by Old Norse gomi "palate," Old High German goumo; related to Lithuanian gomurys "palate," and perhaps from PIE root *ghieh- "to yawn, gape, be wide open."
gum (v.1)
early 14c., gommen, "treat with (medicinal or aromatic) gums," from gum (n.1). In the transferred or figurative sense of "spoil, ruin" (usually with up), as if by some gummy substance, it is first recorded 1901, probably from the notion of machinery becoming clogged. Related: Gummed; gumming.
gum (v.2)
of infants, toothless adults, etc., "to chew or gnaw (something) with the gums," by 1907, from gum (n.2). Related: Gummed; gumming.