Business Cycle
The business cycle is the fluctuation in economic activity that an economy experiences over a period of time. A business cycle is basically defined in terms of periods of expansion or recession. During expansions, the economy is growing in real terms (i.e. excluding inflation), as evidenced by increases in indicators like employment, industrial production, sales and personal incomes. During recessions, the economy is contracting, as measured by decreases in the above indicators. Expansion is measured from the trough (or bottom) of the previous business cycle to the peak of the current cycle, while recession is measured from the peak to the trough.
Source: https://www.investopedia.com/terms/b/businesscycle.asp#ixzz50PmrmFDK
Transmitting business cycle to another country via international trade is one of the challenges that macroeconomists try to explain.