mastic /ˈmæstɪk/ noun4 •A hard, brittle, aromatic and transparent resin produced by this tree and used to make varnishes and chewing gum, and as a flavouring.The mastic, of which the people of Scio gather every year an incredible quantity, is a very rich gum, made use of in medicines, which distils from a shrub called, in Latin, Lentiscus. — 1799 •Any of various cements, usually flexible and waterproof, used as an adhesive, sealant, caulk, or filler.‘They have a few holes here and there. A few. Tiny tiny.’ ‘We could fix those up easy. Mastic cement. Not expensive, boss.’ — 1961 •An evergreen shrub or small tree, Pistacia lentiscus (mastic tree), native to the Mediterranean. •An alcoholic liquor flavoured with this resin.He took a list from the desk and read aloud Fatima’s offerings:— […] four bottles of rare mastic from Scio. — 1913 formsmastics