'dom

arm span, crotch, fathom [RY]

lineal measure, four cubits, fathom, strong jail, dungeon, arm span, crotch, measure equal to 6 feet, fathom measured by the stretching of the arms, arm-spread, a length measure equal to the length of outstretched hands [JV]

1) armspan/ fathom; 2) crotch [IW]