PECULIAR INSTITUTION was a euphemistic term that white southerners used for slavery. John C. Calhoun defended the "peculiar labor" of the South in 1828 and the "peculiar domestick institution" in 1830. The term came into general use in the 1830s when the abolitionist followers of William Lloyd Garrison began to attack slavery. Its implicit message was that slavery in the U.S. South was different from the very harsh slave systems existing in other countries and that southern slavery had no impact on those living in northern states.
Kolchin, Peter. American Slavery: 1619–1877. New York: Hill and Wang, 1993.
Fletcher M.Green/c. p.