Inflation is when prices rise, and deflation is when prices fall. You can have both inflation and deflation at the same time in various asset classes. When taken to their extremes, both are bad for economic growth, but for different reasons. That's why the Federal Reserve, the nation's central bank, tries to control them.
Price changes are merely a symptom of inflation. The original, first definition is an increase in supply of money ( claims on assets and GDP) relative to the supply of assets and GDP. Thus inflation in most economies has already happened to an enormous degree in the past 10 years. Price changes have mostly yet to happen, but could still be forestalled by a balancing deflation.
All goods, assets and incomes will always experience their own rates of price change, depending on their individual relationship with the changing base money.
Central banks have no power to control price changes, but they use various tools (interest rates, repos, QE etc..) as a means to supposedly target a certain price outcome.
These are the reasons there is so much confusion in the measure and definition of the word 'inflation'.