1. The ordinal number of four hundred in counting order
   - four-hundredth

See also: ordinal

• 18
• 18-carat gold
• 18-karat gold
• 180
• 180th
• 1820s
• 1830s
• 1840s
• 1850s
• 1860s
• 1870s
• 1880s
• 1890s
• 18th
• 19
• 190
• 1900s
• 190th
• 1920s
• 1930s
• 1940s
• 1950s
• 1960s
• 1970s
• 1980s