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

• buttonholes
• buttonhole stitch
• buttonholing
• buttonhook
• buttonhooks
• buttoning
• button-mould
• button mushroom
• button quail
• button quails
• buttons
• button scurvy
• button-through
• button up
• buttonwood
• buttonwoods
• buttony
• button your lip
• butt out
• buttress
• buttressed
• buttresses
• buttressing
• buttress-root
• buttress-roots