jetton
Concise Oxford English Dictionary © 2008 Oxford University Press:
jetton /ˈdʒɛt(ə)n/
▶noun a counter or token used as a gambling chip or to operate slot machines.
– origin C18: from Fr. jeton, from jeter ‘throw, add up accounts’ (see jet1); so named because the term was formerly used in accounting.
'jetton' also found in these Oxford entries:

