​ANNA (Hindustani ana), an Indian penny, the sixteenth part of a rupee. The term belongs to the Mahommedan monetary system (see Rupee). There is no coin of one anna, but there are half-annas of copper and two-anna pieces of silver. The term anna is frequently used to express a fraction. Thus an Anglo-Indian speaks of two annas of dark blood (an octoroon), a four-anna (quarter) crop, an eight-anna (half) gallop.