diesel

UK: /ˈdiːz^əl/ US: /ˈdizəl, -səl/ ,(dē′zəl, -səl)

WordReference Random House Learner's Dictionary of American English © 2025

die•sel /ˈdizəl, -səl/   adj. [often: before a noun]

1. Energy, Transport being or referring to a machine or vehicle powered by a diesel engine:
   a diesel locomotive.
2. Energy, Transport of or used by a diesel engine:
   diesel fuel.

n. 

3. Energy [countable] Also, ˈdie•sel ˌen•gine. an engine powered by heated oil, used by buses, trucks, and some cars.
4. Energy, Transport a vehicle powered by a diesel engine:
   [countable] Some diesels have trouble starting on cold days.
5. Energy [uncountable] Also, ˈdie•sel ˌoil. a type of heavy fuel oil used in a diesel engine.

WordReference Random House Unabridged Dictionary of American English © 2025

die•sel  (dē′zəl, -səl), adj. 

1. Energy, Transport noting a machine or vehicle powered by a diesel engine:
   diesel locomotive.
2. Energy, Transport of or pertaining to a diesel engine:
   diesel fuel.

n. 

3. Energy See diesel engine. 
4. Energy, Transport a vehicle powered by a diesel engine.
5. Energy See diesel fuel. 

Also, Diesel. 

• after R. Diesel, the engine's inventor

Die•sel  (dē′zəl, -səl), n. 

Ru•dolf  (ro̅o̅′dolf, -dôlf; Ger. ro̅o̅′dôlf ), 1858–1913, German automotive engineer.

Collins Concise English Dictionary © HarperCollins Publishers::

diesel / ˈdiːz^əl/ noun

1. See diesel engine
2. a ship, locomotive, lorry, etc, driven by a diesel engine
3. 
   short for diesel oil
4. any cola drink