Webster's 1828 Dictionary
CASTILE-SOAP
n.A kind of pure, refined soap.
Webster's 1913 Dictionary
CASTILE SOAP
Cas "tile soap ". Etym: [From Castile, or Castilia, a province in Spain, from which it originally came. ]
Defn: A kind of fine, hard, white or mottled soap, made with olive and soda; also, a soap made in imitation of the above-described soap.
New American Oxford Dictionary
Castile
Cas tile |kaˈstēl kæˈstil | a region in central Spain, on the central plateau of the Iberian peninsula, formerly an independent Spanish kingdom. ORIGIN from French Castille, from Spanish Castilla .
Castile soap
Cas tile soap ▶noun fine, hard white or mottled soap made with olive oil and sodium hydroxide. ORIGIN late Middle English: named after Castile in Spain, where it was originally made.
Oxford Dictionary
Castile
Castile |kaˈstiːl | a region of central Spain, on the central plateau of the Iberian peninsula, formerly an independent Spanish kingdom. ORIGIN from French Castille, from Spanish Castilla .
Castile soap
Cas |tile soap |kaˈstiːl | ▶noun [ mass noun ] fine, hard white or mottled soap made with olive oil and soda.
The Wordsmith Dictionary