In that first assault, Jonathan and his armor-bearer struck down about twenty men in about half an acre of land.
KJV
And that first slaughter, which Jonathan and his armourbearer made, was about twenty men, within as it were an half acre of land, [which] a yoke [of oxen might plow].
ASV
And that first slaughter, which Jonathan and his armorbearer made, was about twenty men, within as it were half a furrow’s length in an acre of land.