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Webster 1913 Edition

Noun.

[

Over

+ L.

plus

more. See

, and cf.

That which remains after a supply, or beyond a quantity proposed; surplus.

Shak.

“The overplus of a great fortune.”

Addison.

Noun.

[over and L. plus, more.]

Surplus; that which remains after a supply, or beyond a quantity proposed. Take what is wanted and return the overplus.

It would look like a fable to report that this gentleman gives away all which is the overplus of a great fortune.

overplus ‎(plural overpluses or overplusses)

That which remains beyond what is necessary or required; a surplus.
- 1603, John Florio, translating Michel de Montaigne, Essayes, London: Edward Blount, OCLC 946730821, II.12:
  Where some for an over-plus, or supererogation have added this necessaity, that they must necessarily accompany them, as well in death, as in life.
- 1609, William Shakespeare, Sonnet CXXXV:
  Thou hast thy Will, And Will too boote, and Will in ouer-plus.