ignition
- 01 B2 Upper Intermediate
the electrical system in a vehicle that starts the engine.
the mechanism or electronic system responsible for igniting the fuel-air mixture in an internal combustion engine.
Simple“The car wouldn't start because there was a problem with the ignition.”
In context“Modern vehicles often replace the traditional ignition system with electronic push-button starts that communicate wirelessly with a key fob.”
Usageusually functions as an uncountable noun when referring to the system as a whole.
Synonyms - 02 B2 Upper Intermediate
the place in a car where you put the key to start the engine.
the physical switch or receptacle into which a key is inserted to activate a vehicle's engine.
Simple“He left his keys in the ignition and accidentally locked the car doors.”
In context“The driver turned the key in the ignition, but the engine only produced a faint clicking sound, suggesting a dead battery.”
Usageoften used with the preposition 'in'.
Synonymsignition switch - 03 C2 Proficiency
the point when a nuclear reaction creates enough energy to keep itself going.
the state in which a thermonuclear fusion reaction becomes self-sustaining, requiring no further external energy input.
Simple“Scientists are working hard to achieve ignition in fusion power plants.”
In context“Achieving fusion ignition represents a major milestone in clean energy research, as it proves the plasma can maintain its own temperature through internal heating.”
Usageuncountable in this specialized physical sense.
Teacher's tipThis is a highly specific term in physics; students will likely only encounter it in science news or academic papers.
From French ignition.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.