fever tree

(noun) any of several trees having leaves or bark used to allay fever or thought to indicate regions free of fever.

(noun) ornamental shrub or small tree of swampy areas in southwestern United States having large pink or white sepals and yielding Georgia bark for treating fever. Synonyms: Georgia bark, bitter-bark, Pinckneya pubens.

(noun) tall fast-growing timber tree with leaves containing a medicinal oil; young leaves are bluish. Synonyms: blue gum, Eucalyptus globulus.

(noun) African tree supposed to mark healthful regions. Synonyms: Acacia xanthophloea.