Definition from Wiktionary, the free dictionary
See also Appendix:Variations of "pres"
Pres or Pres.
- President (used as a title written before a president's name)
This is the customary abbreviation of this term as used in case citations. See, e.g., The Bluebook: A Uniform System of Citation, Nineteenth Edition (2010), "Case Names and Institutional Authors in Citations", Table T6, p. 430-431.