betel
Concise Oxford English Dictionary © 2008 Oxford University Press:
betel /ˈbiːt(ə)l/
▶noun an Asian evergreen climbing plant, whose leaves are chewed as a mild stimulant with betel nuts (the seeds of the areca palm). [Piper betle.]
– origin C16: via Port. from Malayalam veṟṟila.
'betel' also found in these Oxford entries:

