Plentiful means existing in large amounts or numbers, more than enough to meet any need. When apples are plentiful at the orchard in autumn, there are so many that everyone can eat their fill and still have plenty left over. When a library has plentiful books on dinosaurs, you won't struggle to find what you need for your research project.

The word suggests abundance and generosity, with far more available than the minimum required. A plentiful harvest means farmers grew far more crops than expected. Plentiful rainfall means gardens and fields get all the water they need and then some. When something is plentiful, there's no need to worry about running out or rationing carefully.

You might hear people say that opportunities are plentiful in a growing city, meaning there are many chances for people to find work or start businesses. Or a teacher might note that mistakes were plentiful in the first draft of an essay, though that's a different kind of abundance. The opposite of plentiful is scarce, when something is hard to find or in short supply.