Definition of quillay in US English:

quillay

(also quillai)

noun

  • The soapbark tree, Quillaja saponaria.

Origin

Early 18th century. From Mapuche quillai, quillay soapbark tree, also the bark of this tree (also formerly sometimes spelt cúllay; from quillcan to wash); originally via French quillay. Compare Spanish quillay.

Pronunciation

quillay

/kɪˈlʌɪ/