Definition of "contra"

contra

/ˈkɒntɹə/

preposition
1. against; contrary or opposed to; in opposition or contrast to
adverb
comparative more contra, superlative most contra
1. contrary to something
  Quotations
  […] it is useless to pray “Thy kingdom come” and vote contra or stay away from the polls; […]
  1893 November 30, “The W.C.T.U. Convention. Interesting Reports Considered in Relation to the Several Departments of the Work. Suggested Lines of Development—Programme for the Closing Day.”, in The Daily Colonist, volume LXX, number 148, Victoria, B.C., page 3, column 1
noun
plural contras
1. (business) A deal to swap goods or services.
2. (politics, derogatory) A conservative; originally tied to Nicaraguan counter-revolutionaries.
3. (accounting, often attributive) An entry (or account) that cancels another entry (or account).
4. (music, informal) Any of the musical instruments in the contrabass range, e.g. contrabassoon, contrabass clarinet or, especially, double bass.
5. (dance) A contra dance.
6. (obsolete, US, New England, dance) A country dance.
  Quotations
  Folk histories record that contras were gradually displaced by the introduction of the quadrille and the new couple dances.
  2001, Ellen Koskoff, editor, The Garland Encyclopedia of World Music: North America, Garland Publishing, page 232
verb
third-person singular simple present contras, no present participle, no simple past or past participle
1. (accounting) To undo; to reverse.