1.Verbto make something inactive or no longer effective
"deactivate an account; deactivate a device; The technician deactivated the alarm system before repairs began.; You should deactivate your old account to protect your privacy."
2.Verbto prevent the action of a biochemical agent (such as an enzyme)
"chemically deactivate; The chemical agent was deactivated by exposure to heat."
3.Verbto remove a person or piece of hardware from active military service