aniseed
Small grey-green seeds of the anise plant with a sweetish, liquorice-like aroma.
Aniseed is the dried fruit of the anise plant and tastes sweetish and of liquorice, warmer and rounder than fennel. It is sold in the spice aisle of larger supermarkets, and otherwise in Turkish or Middle Eastern grocers, health food shops or from online spice suppliers.
Substitute:
Fennel seed comes closest but is milder and less sweet, so use a little more; ground star anise matches the liquorice note but is much stronger and should be used sparingly.