12 letters · 16 points in Scrabble
noun a particle that has the same mass as another particle but has opposite values for its other properties; interaction of a particle and its antiparticle results in annihilation and the production of rad
originEtymology tree Proto-Indo-European *h₂ent- Proto-Indo-European *-s Proto-Indo-European *h₂énts Proto-Indo-European *-i Proto-Indo-European *h₂énti Ancient Greek ᾰ̓ντῐ́ (ăntĭ́) Ancient Greek ἀντι- (anti-)der. English anti- English particle English antiparticle From anti- + particle.
Etymology from Wiktionary, CC BY-SA 3.0