catechu
noun
cat·e·chu ˈka-tə-ˌchü 
-ˌshü
: any of several dry, earthy, or resinous astringent substances obtained from tropical plants of Asia: such as
a
: an extract of the heartwood of an acacia (Acacia catechu)
b
: gambier
Word History
Etymology
probably modification of Malay kachu, of Dravidian origin; akin to Tamil & Kannada kācu catechu
First Known Use
1683, in the meaning defined above
Medical Definition
catechu
noun
cat·e·chu ˈkat-ə-ˌchü, -ˌshü
: any of several dry, earthy, or resinous astringent substances obtained from tropical plants of Asia: as
a
: an extract of the heartwood of a tropical acacia tree (Acacia catechu) of southern Asia that was formerly used in medicine
b
: gambier