hot-bulb

adjective

: having an ignition system in which the charge is ignited by spraying it into a separate chamber kept above the ignition temperature of the charge by the heat of compression

—used of a semidiesel engine

The Ultimate Dictionary Awaits

Expand your vocabulary and dive deeper into language with Merriam-Webster Unabridged.

1. Expanded definitions
2. Detailed etymologies
3. Advanced search tools
4. All ad-free

Discover what makes Merriam-Webster Unabridged the essential choice for true word lovers.

Start Your Free Trial Now