Activise is an antonym of passivise.
As a verb passivise is
(british|grammar) to render into the passive form.
activise
Not English
Activise has no English definition. It may be misspelled.
passivise
English
Alternative forms
*passivize
Verb
(passivis)
(British, grammar) To render into the passive form.
Antonyms
*activise
Derived terms
*passivisable