What does "cornucopia" mean? and is it a commonly used expression? I feel like it could be used to express something metaphorically.

Native speaker’s answer
Rebecca
A "cornucopia" is an abundant, diverse supply of things. In history, it was represented in the shape of a goat's horn, called the horn of plenty. Now, it's a word used to describe a multitude of good things of a specified kind. Ex: The festival was a cornucopia of delightful pastries and baked goods. Ex: The toy story was a cornucopia of colorful toys and devices.