Inflation
Etymology
From Latin inflare, "to blow into, puff up" (in-, "into," plus flare, "to blow"). For centuries it described swelling with air, as a balloon inflates. American writers in the mid-1800s applied it to the money supply being "puffed up" with extra currency, and the modern sense of rising prices grew directly out of that image.
noun · /in-FLAY-shun/
A general, sustained rise in prices across an economy, so each unit of money buys a little less than it did before.
What it names
It explains why your salary can go up while you feel poorer — the yardstick you measure wealth with is quietly shrinking.
Example
With inflation running near seven percent, the raise she fought for barely kept her even.
Related idea
Do not confuse it with deflation, its mirror image: inflation is prices climbing, deflation is prices falling.