| Noun | 1. | mastic - an aromatic exudate from the mastic tree; used chiefly in varnishesnatural resin - a plant exudate |
| 2. | mastic - a pasty cement used as an adhesive or filler cement - something that hardens to act as adhesive material filler - used for filling cracks or holes in a surface | |
| 3. | mastic - an evergreen shrub of the Mediterranean region that is cultivated for its resin genus Pistacia, Pistacia - a dicotyledonous genus of trees of the family Anacardiaceae having drupaceous fruit |