Origins
The English word 'inflation' entered the language around 1340 from Latin 'inflātiō, inflātiōnis' (a blowing up, a swelling, a puffing up, a distension), from the verb 'inflāre' (to blow into, to puff up, to swell), composed of 'in-' (into) and 'flāre' (to blow). The PIE root is *bʰleh₁- (to blow, to swell), which through Germanic paths gave English 'blow,' 'blast,' 'bladder,' and 'blaze,' and through Latin gave 'flavor' (originally the smell that 'blows' from something), 'flatulent' (full of blowing), and 'conflate' (to blow together).
For nearly five centuries after entering English, 'inflation' had nothing to do with economics. Its primary meanings were medical (the swelling of a body part with air or fluid), theological (spiritual pride — the sin of being 'puffed up' with self-importance, as discussed by Augustine and other Church Fathers), and general (the act of blowing air into something). The medical sense appears in Chaucer's time; the theological sense was prominent in religious writing through the seventeenth century.
The economic sense of 'inflation' emerged in the 1830s and 1840s in American English, initially referring to the expansion of the money supply — the 'blowing up' of the amount of paper currency in circulation, particularly during the debates over banking policy that dominated American politics in Andrew Jackson's era. The metaphor was vivid: just as blowing air into a balloon makes it swell without adding substance, printing more money makes prices swell without adding real value. The image of inflated currency as a puffed-up, insubstantial thing carried moral overtones that echoed the theological sense of inflation as pride.
Figurative Development
By the late nineteenth century, 'inflation' had shifted from describing the cause (expansion of money supply) to describing the effect (rising prices). This semantic shift reflects a change in economic understanding: modern economics recognizes that price increases can result from multiple factors — demand pressure, supply shocks, wage increases, expectations — not just monetary expansion. The word now describes the phenomenon rather than the mechanism, though the 'blowing up' metaphor remains embedded in the term.
The opposite of inflation is 'deflation' — a general decrease in prices — formed with the Latin prefix 'dē-' (down, away from). 'Disinflation' describes a decrease in the rate of inflation (prices still rising, but more slowly). 'Hyperinflation' describes inflation so extreme that it destroys a currency's value: Germany's Weimar Republic in 1923, Zimbabwe in 2008, Venezuela in the 2010s. 'Stagflation' — a portmanteau of 'stagnation' and 'inflation' coined in the 1960s — describes the economically painful combination of high inflation and high unemployment.
The Latin verb 'flāre' produced a remarkable range of English words. 'Deflate' (to blow down), 'conflate' (to blow together, to merge), 'insufflation' (blowing into, used in medical and religious contexts), 'soufflé' (a French culinary term meaning 'blown up,' from the same root via Old French 'souffler'). The connection between 'inflation' and 'flatulence' is genuine and frequently noted: both involve unwanted and excessive blowing up. The humor of this connection should not obscure the etymological insight: the human experience of swelling, puffing, and distension was mapped onto the economic experience of rising prices by speakers who felt the same visceral discomfort in both.
Latin Roots
Inflation has been a persistent feature of economic life since the invention of money. The Roman Empire experienced significant inflation, partly caused by the debasement of coinage — emperors reduced the silver content of coins while maintaining their face value, a physical version of monetary inflation. The Price Revolution of the sixteenth and seventeenth centuries, when gold and silver from the Americas flooded Europe, caused sustained price increases that transformed European economies and social structures. In each case, the experience was the same: money buying less, prices rising, savers losing value.
In modern central banking, managing inflation is considered a primary responsibility. The concept of an 'inflation target' — a desired rate of price increase, typically around 2 percent annually — reflects the view that moderate inflation is healthy for an economy (encouraging spending and investment) while high inflation is destructive (eroding savings and creating uncertainty). This careful calibration would have been incomprehensible to the medieval writers who used 'inflation' to mean sinful pride — but the underlying metaphor persists: too much puffing up is dangerous, whether in the soul or in the economy.