1Chiefly in North America before the War of Independence: a reissue of bills, shares, currency, etc. Compare "emission". Now rare (chiefly historical in later use).
2Emission again of something which has been absorbed; (Physics) emission of radiation after previous absorption. Also: an instance of this; a thing that is re-emitted. rare before mid 20th century.
Mid 18th century; earliest use found in William Douglass (?1691–1752). From re- + emission, in sense 1 after re-emit.