What is "c18"

sym. the 1700s or 18th century.

C18 may refer to:

• HMS C18, a submarine
• Sauber C18, a Formula One racing car
• Caldwell 18 ( NGC 185), a dwarf spheroidal galaxy of the Local Group in the constellation Cassiopeia
• French Defence, Encyclopaedia of Chess Openings code

and also :

• Combat 18, a British neo-Nazi organization
• The 1938 Chrysler Royal C18
• The C-18, a military cargo version of the Boeing C-137 Stratoliner
• The 18th century (1701–1800 AD)
• an octadecyl-type hydrocarbon with 18 carbon atoms, such as
  • fatty acids such as
    • stearic acid, CHO
    • oleic acid CHO
  • C18 bonded silica stationary phase column, a type of reversed-phase chromatography column
• IEC 60320 C18, a power connector
• Malignant neoplasm of colon ICD-10 code