| trifoliate | (adj) (of a leaf shape) having three leaflets, Syn. trifoliolate, trifoliated |
| trifoliate orange | (n) small fast-growing spiny deciduous Chinese orange tree bearing sweetly scented flowers and decorative but inedible fruit: used as a stock in grafting and for hedges, Syn. trifoliata, Poncirus trifoliata, wild orange |
| water shamrock | (n) perennial plant of Europe and America having racemes of white or purplish flowers and intensely bitter trifoliate leaves; often rooting at water margin and spreading across the surface, Syn. marsh trefoil, bogbean, bog myrtle, Menyanthes trifoliata, buckbean |