Easton's Bible Dictionary

Farthing

(1.) Matt. 10:29; Luke 12:6. Greek assarion, i.e., a small as, which was a Roman coin equal to a tenth of a denarius or drachma, nearly equal to a halfpenny of our money.

(2.) Matt. 5:26; Mark 12:42 (Gr. kodrantes), the quadrant, the fourth of an as, equal to two lepta, mites. The lepton (mite) was the very smallest copper coin.