Greek δραχμή. Also called Drachmae, Piece of silver, drachme.
The Greek silver coin, worth about the same as a denarius — a day's wage, in Greek money.
Wage
1 day's wage (1 day's wage).
Reckoned from its rough parity with the denarius.
Mass
3.4–4.3 g (0.12–0.152 oz).
Reckoned from surviving Greek drachmas, which varied by city.
Diameter
1.5–1.8 cm (0.591–0.709 in).
Reckoned from surviving Greek drachmas, which varied by city.
A drachma is the Greek counterpart of the denarius and traded at roughly parity with it, so it is also about a day's work. It appears in the parable of the woman who loses one of her ten and lights a lamp to sweep the house until she finds it — which reads as fussing over small change until you notice that ten drachmas is a fortnight's wages, and quite possibly her dowry.
Sizes are the range of surviving examples, and coins of one name varied from mint to mint. Bronze paid for small things and silver for wages and taxes: the widow gave two lepta (Mark 12:42), the temple tax was a didrachma (Matthew 17:24), and a stater paid it for two (17:27).