Definition
In arithmetic, the amount left over after one number has been divided into another a whole number of times. In a broader sense, what is left of a quantity after a portion has been taken away or accounted for.
Plain English
What's left over. After you divide, subtract, or remove part of something, the remainder is the part that's still there.
Context Anchor
Seen in aviation maintenance math, parts counts, measurement work, and weight-and-balance calculations.
Derivation
From the Old French 'remaindre,' meaning 'to stay behind' or 'to be left.' The same root gives us 'remain.' The remainder is literally what remains after the rest has been taken or used.
Why Pilots Care
A small remainder can still matter in aviation calculations. Ignoring what is left over can lead to an incorrect total, an uneven parts count, or a bad measurement decision.
Intuition Check
Do not treat remainder as a vague word meaning “whatever is left.” In a calculation, the remainder is a specific leftover amount that must be accounted for.
Example Sentence 1
After dividing the total fuel load by the number of tanks, the technician noted the remainder to ensure none was unaccounted for.
Example Sentence 2
Subtract the used fasteners from the bin count and log the remainder before closing the work order.