from the root of zeugnumi (to join, especially by a "yoke"); a coupling, i.e. (figuratively) servitude (a law or obligation); also (literally) the beam of the balance (as connecting the scales):--pair of balances, yoke.
a yoke
a yoke that is put on draught cattle
metaph., used of any burden or bondage
as that of slavery
of troublesome laws imposed on one, esp. of the Mosaic law, hence the name is so transferred to the commands of Christ as to contrast them with the commands of the Pharisees which were a veritable 'yoke'; yet even Christ's commands must be submitted to, though easier to be kept