Definition
A spark plug constructed with a central electrode made of one metal (typically a precious metal such as platinum or iridium) and ground electrodes made of a different, less expensive metal. This mixed-metal construction extends service life and improves erosion resistance compared with conventional all-nickel-alloy plugs, while keeping cost lower than a fully precious-metal plug.
Plain English
A spark plug that uses two different metals for its electrodes — usually a tougher, longer-lasting metal in the center and a more standard metal on the outside.
Context Anchor
Seen in piston-engine maintenance, spark plug inspection, replacement, and approved parts records.
Derivation
Hybrid comes from the Latin hybrida, meaning a mix of two different things. Here it describes a spark plug that mixes two different electrode metals in one component.
Why Pilots Care
Hybrid plugs typically last longer and resist electrode wear better than standard plugs, which can mean fewer plug changes and more consistent ignition performance — but they still must match the engine manufacturer's approved part numbers.
Intuition Check
Hybrid does not mean the airplane has two kinds of power, like fuel and electric power. Here it means the spark plug itself uses a mix of electrode materials.
Example Sentence 1
The mechanic recommended hybrid spark plugs for the overhauled engine because they last longer between replacements.
Example Sentence 2
The hybrid spark plugs maintained consistent ignition across the full power range of the turbocharged engine.