In the modern age, cornucopias are represented as wicker baskets that look like a funnel, containing various fruit and vegetables.
However the origin of the term comes from ancient Greece. In Greek mythology, Zeus accidentally broke off the horn of a goat (turning it into a unicorn). The horn had the power of granting wishes. But since the goat/unicorn was a, well…a goat/unicorn, it wanted only fruits and vegetables.
That’s one version of the origination myth.
Another states that Zeus accidentally broke the horn of a nymph who was a goat tender and granted her a replacement horn.
That’s all I’m going to say on the subject of Zeus and Nymphs because I still want to keep the family friendly tag.