Definition of ague tree in English:

ague tree

noun

historical
  • The sassafras, Sassafras albidum, parts of which (especially the root and bark) were formerly used in the treatment of fevers.

Origin

Late 16th century; earliest use found in John Gerard (c1545–1612), herbalist. From ague + tree, with allusion to the use of the root of this tree in the treatment of fevers.

Pronunciation

ague tree

/ˈeɪɡjuː ˌtriː/