a.
1.
Smart, stinging, stimulating, pricking, sharp, biting, mordant, burning, caustic, pyrotic, hot, peppery, piercing, penetrating, piquant, acrid.
2.
Acute, keen, trenchant, cutting, acrimonious, severe, peevish, tart, waspish, distressing, poignant, smart, painful, satirical, pointed.