The 4-amino-1,8-naphthalimide-Tröger's base fluorophore, TBNap-TPy, adorned with phenyl-terpyridine moiety was synthesised and assessed for its aggregation-induced emission (AIE) behaviour. TBNap-TPy was further employed as a fluorescent sensor for the discriminative sensing of π-electron-deficient nitroaromatic; the TBNap-TPy displaying the largest fluorescence quenching with high selectivity for picric acid, a harmful environmental pollutant widely used in the dye industries.