Plethora implies an overabundance, sometimes to the point of being excessive or burdensome. It emphasizes the sheer volume and can be used in a slightly negative context.
Cornucopia, on the other hand, evokes a rich and overflowing abundance. It carries a more positive connotation, often associated with prosperity, plenty, and festivity.
Here's a simple way to understand the difference:
* Plethora: "There was a plethora of information on the internet, making it hard to find what I needed." (Suggests too much, potentially overwhelming)
* Cornucopia: "The farmer's market offered a cornucopia of fresh fruits and vegetables." (Suggests delightful and abundant variety)
In summary, plethora focuses on quantity and excess, while cornucopia emphasizes variety and positive abundance.