Final answer:
Contagious diffusion is the geographic term that refers to the rapid, widespread diffusion of a feature or trend throughout a population. It occurs when a cultural trait spreads rapidly and widely from one person or place to another.
Step-by-step explanation:
The geographic term that refers to the rapid, widespread diffusion of a feature or trend throughout a population is contagious diffusion. Contagious diffusion occurs when a cultural trait spreads rapidly and widely from one person or place to another, similar to the way a contagious disease spreads. An example of contagious diffusion is the spread of popular music or fashion trends through a population.