Thomassin may refer to: People Surnames Claude Thomassin, French bow maker, or Archetier Florence Thomassin, French actress and sculptor Laurie Thomassin, French retired breaststroke swimmer Louis Thomassin, French theologian and Oratorian Louis Thomassin (archetier), French bow maker, or Archetier Antoine de Thomassin de Peynier (1731–1809), officer of the French Royal Navy Places Thomassin, a neighborhood of Pétion-Ville, Haiti