Definition
A long, thin metal rod inserted into the engine's oil sump through a sealed tube, used to measure the quantity of engine oil. The lower end is marked with graduations (typically in U.S. quarts) showing the current oil level when the stick is withdrawn, wiped, reinserted, and read.
Plain English
A marked metal stick that you pull out of the engine to check how much oil is inside. The wet line on the stick shows the oil level against the markings.
Context Anchor
Used during the preflight inspection when checking engine oil quantity before starting the engine.
Derivation
From 'dip' (to lower briefly into a liquid) and 'stick' (a thin rod). The name describes the action: you dip the stick into the oil to measure it.
Why Pilots Care
Confirms adequate lubrication before flight to prevent engine damage or failure.
Analogy
Works exactly like the oil check stick in a car engine for quick level verification.
Intuition Check
Do not treat the oil dipstick as just a cap or handle. In preflight use, it is a measuring tool used to confirm the engine has the required oil quantity.
Example Sentence 1
During preflight, the pilot pulled the oil dipstick, wiped it clean, reinserted it fully, and then withdrew it again to read the oil level.
Example Sentence 2
With the oil dipstick showing low, the pilot added the correct oil type before engine start.