xi /zī, ksī or ksē/

1. The fourteenth letter of the Greek alphabet (Ξ or ξ), corresponding to X
2. As a numeral ξˈ = 60, ˌξ = 60000

• supersonics
• supersophisticated
• supersound
• supersounds
• superspecies
• superspeed
• superspeeds
• superspies
• superspy
• superstar
• superstardom
• superstardoms
• superstars
• superstate
• superstates
• suretied
• sureties
• surety
• suretying
• suretyship
• suretyships
• surf
• SURF
• surface
• surface-active