activator

[ ak-tuh-vey-ter ]

noun

1. a person or thing that activates.
2. Chemistry, Biochemistry. a catalyst.
3. any impurity in a mineral that causes luminescence. Compare inhibitor ( def 3 ).
4. Orthodontics. a removable appliance, usually of hard plastic, that is worn in the mouth instead of a fixed appliance to help align the teeth and improve the relationship of the lower jaw to the upper.

Other Words From

• non·acti·vator noun

Word History and Origins

Origin of activator¹

activate + -or ²

Example Sentences

Just like with color, fluorescence in minerals is often the product of impurities, called activators.

From Popular-Science

Before you add activator, have a plan for holding the pieces together if you’re dealing with separate pieces.

From Washington Post

The color will change very little after the activator is added, Geronimo said.

From Washington Post

Once you mix in the activator, you’ll have five to 15 minutes of working time.

From Washington Post

The adhesive should be fully set in 15 to 40 minutes, depending on the temperature, how much activator you used and how much material you mixed.

From Washington Post

TA-65, the new study claims, is a “telomerase activator”—that is, it turns on telomerase in cells.

From The Daily Beast

The Black Doctor closed his eyes wearily and flipped an activator switch.

From Project Gutenberg

I call him Homo Causacadere, the fall causer, whose activator is hostility.

From Project Gutenberg

Finally, he poked the activator bar, and watched as the machine spat out tape.

From Project Gutenberg

They may have been, and the use of the activator may have been extorted from one of them.

From Project Gutenberg

Skordran Kirv used a door-activator to slide open a hidden door.

From Project Gutenberg