/reɪt/
[noun] A measure of how fast something happens, how much something costs, or how good something is compared to others. For example, the speed of a car, the price of a hotel room, or a score given to a film.
Every time you check a hotel rate or movie rating, you are using a word born from a Roman legal formula for calculating taxes.
The word 'rate' travels to us from the Latin phrase 'pro rata parte', meaning 'according to the calculated part'. The key word here is 'rata', which is the past participle of the Latin verb 'reri', meaning 'to calculate' or 'to think'. Roman administrators used this expression constantly in legal and financial documents to describe how taxes, debts, or shares should be divided proportionally among people. The idea was precise and mathematical — not a rough guess, but a carefully worked-out portion.
From Latin, the word moved into Medieval Latin as 'rata', a shorthand for the full phrase, used in official documents across Europe throughout the early medieval period. As Latin remained the language of law, the Church, and scholarship, this term stayed alive in administrative writing long after the fall of Rome. It was particularly common in contracts and ledgers, where scribes needed a word for a fixed proportion or assessed value.
The word entered English in the 15th century, borrowed directly from Medieval Latin 'rata' or from Old French 'rate', which had taken the same Latin root through the same bureaucratic channels — Latin rata → Old French rate → Middle English rate. At first, English used it almost exclusively in financial and legal contexts, meaning a fixed price, a tax assessment, or a proportional charge. Town records from the 1400s mention rates set by local authorities for goods, labour, and land.
Over the 16th and 17th centuries, the meaning broadened considerably. English speakers began using 'rate' to describe the speed at which anything happened — the rate of a river's flow, the rate at which a fever progressed, the rate of cannon fire. This shift from proportion to speed made perfect sense: both meanings involve measuring one thing against another, whether it is a share of a total or a quantity measured against time. The word was doing the same mathematical work, just in a new setting.
By the 18th and 19th centuries, 'rate' had acquired its evaluative sense — rating something meant placing it in a rank or category, judging its quality. This gave us the verb 'to rate', meaning to assess or assign a value, and eventually the modern world of star ratings, credit ratings, and performance reviews. The Latin tax official carefully dividing up a bill would barely recognise the word in a cinema app, but the underlying logic — measuring, comparing, and assigning a calculated value — has never changed.