The logistic curve, also known as the sigmoid curve, is a mathematical model used to describe the growth of a population over time. Synonyms for the logistic curve include the S-curve and the diffusion curve. The S-curve refers to the shape of the curve, which starts out slow, picks up speed, and then levels off as the population reaches its carrying capacity. The diffusion curve refers to the spread of an idea or innovation through a population over time, which can also be modeled with the logistic curve. Other synonyms for the logistic curve include the logistic function and the growth model, as it is often used to model growth patterns in various fields like biology, economics, and ecology.