Main entry: activate
Definition: make active or more active
Usage: activate an old file
Main entry: activate
Definition: make (substances) radioactive
Definition: aerate (sewage) so as to favor the growth of organisms that decompose organic matter
Main entry: activate
Definition: make more adsorptive
Usage: activate a metal
Main entry: set off, spark, spark off, activate, actuate, trigger, trigger off, trip, touch off
Definition: put in motion or move to act
Usage: trigger a reaction; actuate the circuits