reynolds

Reynolds is a surname of English and Irish origin. It is a patronymic derived from the given name Reynold, a medieval form of Reginald, and has become widespread in the English-speaking world. The name has many variants, including Reynold and Reginald, and in some Irish contexts appears in the form O’Reynolds.

Reynolds also appears as a place name and in the names of organizations and brands linked to people bearing the surname. In science, the term Reynolds is associated with the Reynolds number, a fundamental dimensionless quantity in fluid mechanics used to predict flow regimes and the onset of turbulence. The Reynolds number is defined as Re = ρ v L / μ and was introduced by Osborne Reynolds in his investigations of pipe flow.

In industry, Reynolds Metals Company is known for producing aluminum and for Reynolds Wrap, a widely used brand of household aluminum foil. Reynolds American Incorporated was a major U.S. tobacco company that was acquired by British American Tobacco in 2017, forming a larger corporate entity under BAT.

Notable people with the surname include Osborne Reynolds, a British engineer and physicist who formulated the Reynolds number, and the contemporary actor Ryan Reynolds. The name also appears in numerous other contexts, including various towns, counties, and geographic features in the United States and other countries.