- noun a figure, in the form of a percentage, which shows the amount by which inflation has increased over a period of time, usually a year.
- noun the percentage increase in prices over a twelve-month period. The inflation rate in the UK is calculated on a series of figures, including prices of consumer items, petrol, gas and electricity and interest rates. This gives the underlying inflation rate which can be compared to that of other countries. The calculation can also include mortgage interest and local taxes which give the headline inflation figure; this is higher than in other countries because of these extra items.