Definition of "plenty"

During this season of distress, the discouragements to marriage, and the difficulty of rearing a family are so great that population is at a stand. In the mean time the cheapness of labour, the plenty of labourers, and the necessity of an increased industry amongst them, encourage cultivators to employ more labour upon their land, to turn up fresh soil, and to manure and improve more completely what is already in tillage

1798, Thomas Malthus, An Essay on the Principle of Population

For the likes of her, the down-at-heels support of Hoboken pier was plenty good enough.

1932, Delos W. Lovelace, King Kong, published 1965, page 1

Seeing clichés mimicked this skillfully is plenty hilarious.

2014 June 26, A. A. Dowd, “Paul Rudd and Amy Poehler Spoof Rom-com Clichés in They Came Together”, in The A.V. Club‎, archived from the original on 7 December 2017

if reasons were as plenty as blackberries

1597, Shakespeare, Henry IV, Part I, Act I, Scene IV

There are, among the Irish, men of as much worth and honour as any among the English: nay, to speak the truth, generosity of spirit is rather more common among them. I have known some examples there, too, of good husbands; and I believe these are not very plenty in England.

1749, Henry Fielding, The History of Tom Jones, a Foundling, volumes (please specify |volume=I to VI), London: A[ndrew] Millar, […]

Radishes are very plenty. Of cabbages a few heads of this year's crop have come to hand this week, and sold readily at quotations; […]

1836, The American Gardener's Magazine and Register, volume 2, page 279