Definition of "substraction"

substraction

noun
countable and uncountable, plural substractions
1. (obsolete or non-native speakers' English) Subtraction.
  Quotations
  The plasterer doth make his figures by addition, and the carver by substraction.
  1624, Henry Wotton, The Elements of Architecture, […], London: […] Iohn Bill
  [in title]
  1999, A. Quinquis, C. Ioana, H. Thomas, “Noise substraction for improving the localisation of an underwater mobile”, in Oceans '99: Riding the Crest into the 21st Century. IEEE Conference Proceedings