Plenty has 9 different meanings across 5 categories:
Noun · Adverb · Pron · Det · Proper Noun
a full supply
"there was plenty of food for everyone"
(often followed by `of') a large number or amount or extent
"a batch of letters"
"a deal of trouble"
"a lot of money"
"he made a mint on the stock market"
"see the rest of the winners in our huge passel of photos"
"it must have cost plenty"
"a slew of journalists"
"a wad of money"
A more-than-adequate amount.
"There is plenty of time left to finish all the tasks before the deadline arrives."
In plain English: Plenty is a large amount of something that is more than enough.
"There is plenty to eat at the potluck dinner."
Usage: Use "plenty" as a noun to describe an abundance of something when it functions as the subject or object of a sentence, often following phrases like "there is." It should not be used after prepositions like "of" in formal writing unless part of the idiomatic expression "plenty of."
plentiful
"After the rainstorm, there was plenty of fresh water flowing from the creek for everyone to drink."
In plain English: Plenty means having more than enough of something so you don't need any more.
"There are plenty of apples left for everyone to eat."
Usage: Use plenty as an adjective only before a noun that already has its own quantifier, such as in "a plenty of people," though this construction is often considered awkward or nonstandard. In most cases, it is better to use plenty as a pronoun (e.g., "there is plenty") or pair it with a determiner like enough or sufficient to describe abundance.
More than sufficiently.
"The garden was flooded with plenty of rain, so we didn't need to water our plants at all."
In plain English: You use plenty to describe doing something with great enthusiasm or in large amounts.
"There is plenty of time to finish the project before the deadline."
Usage: Use plenty as an adverb only when modifying verbs to indicate that something happens with ample quantity or frequency, such as in "we ate plenty." It should never be used to modify adjectives or other adverbs, which requires the word "very" instead.
More than enough.
"There is plenty of time to finish the project before the deadline."
much, enough
"There is plenty of time left to finish the project before the deadline."
A village in Saskatchewan, Canada.
"When we finally reached Plenty last night, the small Saskatchewan town was already asleep under a blanket of snow."
Plenty entered Middle English as "plentie" from Old French and ultimately derives from the Latin word for fullness. Its meaning has remained consistent throughout its history, describing a state of being completely filled or abundant.