ENERGY

n. vitality, forcefulness, vivacity, liveliness, vigour, animation, spirit, force, dynamism, drive, verve, dash, élan, intensity, power, determination, puissance, strength, might, Colloq pep, vim and vigour, US stick-to-it-iveness, get-up-and-go, zip, zing At seventy, she just couldn't put as much energy into her performance as she once did