verb. ['ˈæktəˌveɪt'] put in motion or move to act.
verb. ['ˈæktəˌveɪt'] make active or more active.
verb. ['ˈæktəˌveɪt'] make more adsorptive.
verb. ['ˈæktəˌveɪt'] make (substances) radioactive.
verb. ['ˈæktəˌveɪt'] aerate (sewage) so as to favor the growth of organisms that decompose organic matter.