Definition
A chemical solvent or cleaning agent used to remove grease, oil, and similar petroleum-based residues from aircraft engines, components, and structural parts during maintenance.
Plain English
A liquid cleaner that strips off oily, greasy build-up so mechanics can inspect or work on parts that would otherwise be too dirty to handle.
Context Anchor
Seen during aircraft cleaning, engine-area maintenance, surface preparation, and parts cleaning.
Derivation
Built from the prefix de- (meaning 'remove') and grease. The word literally describes its job: something that takes grease away.
Why Pilots Care
Proper cleaning reveals hidden damage, prevents corrosion, and ensures components function safely.
Intuition Check
Do not assume any strong cleaner is a safe degreaser for aircraft use. A degreaser must be suitable for the material being cleaned and used according to the maintenance instructions.
Example Sentence 1
The mechanic sprayed degreaser on the engine case before inspecting it for oil leaks.
Example Sentence 2
Only approved degreaser was applied to the landing gear struts to avoid corrosion on the metal.