n. & v.
n. 1 a a viscous secretion of some trees and shrubs that hardens on drying but is soluble in water (cf. RESIN). b an adhesive substance made from this. 2 US chewing gum. 3 = GUMDROP. 4 = gum arabic. 5 = gum-tree. 6 a secretion collecting in the corner of the eye. 7 US = GUMBOOT.
v. (gummed, gumming) 1 tr. smear or cover with gum. 2 tr. (usu. foll. by down, together, etc.) fasten with gum. 3 intr. exude gum. gum arabic a gum exuded by some kinds of acacia and used as glue and in incense. gum benjamin benzoin. gum dragon tragacanth. gum juniper sandarac. gum resin a vegetable secretion of resin mixed with gum, e.g. gamboge. gum-tree a tree exuding gum, esp. a eucalyptus. gum up 1 (of a mechanism etc.) become clogged or obstructed with stickiness. 2 colloq. interfere with the smooth running of (gum up the works). up a gum-tree colloq. in great difficulties.
[ ME f. OF gomme ult. f. L gummi, cummi f. Gk kommi f. Egypt. kemai ]