Elektaroon (Af-Ingiriis: Electron; summad: -e) ama danab dhaliye waa saxar atam la' una sameysan qiyaastii qaab kubbadeed kana kooban atamka waxa uu wataa Saldanab tabane ah. Mana la ogaan in uu leeyahay saxarro yaryar, sidaad daraadeed waxaa loo gartay in uu yahay Saxar saleed. Elektaroonku wuxuu leeyahay cuf qiyaastii u dhigma 1/1836 ee ka mid ah cufka Borotoon. Waxyaalaha innagu wareegsan oo dhan waxay ka kooban yihiin atamo yar-yar. Qeyb muhiim ah oo ka mid ah atamka waa elektaroon. Baaritaan uu sameeyey nin aqoon u leh cilmiga kimisteriga, ayuu ku ogaaday in wadarta culayska afar elektaroon tahay qiyaastii 3,644·10-30 kg.