What expression describes the tremendous change in population following world war 11?

The expression that describes the tremendous change in population following World War II is the "Baby Boom." This period, roughly from 1946 to 1964, saw a significant increase in birth rates as returning soldiers started families, leading to a demographic shift in many countries, particularly in the United States. The Baby Boom had lasting social and economic impacts, influencing everything from education to housing and labor markets in subsequent decades.