1 make active; bring into action.
2 Chem. cause reaction in; excite (a substance, molecules, etc.).
3 Physics make radioactive.
activated carbon carbon, esp. charcoal, treated to increase its adsorptive power. activated sludge aerated sewage containing aerobic bacteria.
activation n. activator n.
accelerate, actuate, animate, arouse, atomize, awaken, bombard, charge, cleave, contaminate, cross-bombard, energize, fission, galvanize, get going, impel, infect, initiate, irradiate, mobilize, motivate, move, nucleize, poison, prompt, radiumize, rally, reactivate, recharge, remilitarize, rouse, set going, set in motion, smash the atom, start, stimulate, stir, switch on, trigger, turn on, wake, waken