APR
Etymology
An acronym for "annual percentage rate", a regulatory coinage designed to standardize how lenders disclose borrowing costs. "Percentage" traces to Latin "per centum" (by the hundred). Flag it as a legal and financial invention, created so that offers could be compared on a single common figure.
noun · /ay-pee-AR/
The yearly cost of borrowing, expressed as a percentage that includes interest plus most fees.
What it names
The number that lets you compare loans honestly, because it folds fees into the interest rate rather than hiding them.
Example
The card’s low teaser interest looked cheap until she read the 29% APR in the fine print.
Related idea
Distinguish APY (annual percentage yield): APR ignores the effect of compounding, while APY includes it, so a saver wants a high APY and a borrower wants a low APR.