Ambidexter
Webster's Dictionary [1]
(1): (n.) A double-dealer; one equally ready to act on either side in party disputes.
(2): (n.) A person who uses both hands with equal facility.
(3): (a.) Using both hands with equal ease.
(4): (n.) A juror who takes money from both parties for giving his verdict.
Kitto's Popular Cyclopedia of Biblial Literature [2]
Ambidexter, one who can use the left hand as well as the right, or, more literally, one whose hands are both right hands. It was long supposed that both hands are naturally equal, and that the preference of the right hand, and comparative incapacity of the left, are the result of education and habit. But it is now known that the difference is really physical, and that the ambidexterous condition of the hands is not a natural development.
The capacity of equal action with both hands was highly prized in ancient times, especially in war. Among the Hebrews this quality seems to have been most common in the tribe of Benjamin, as all the persons noticed as being endued with it were of that tribe. By comparing Judges 3:15; Judges 20:16, with 1 Chronicles 12:2, we may gather that the persons mentioned in the two former texts as 'left-handed,' were really ambidexters. In the latter text we learn that the Benjamites who joined David at Ziklag were 'mighty men, helpers of the war. They were armed with bows, and could use both the right hand and the left in hurling [slinging] and shooting arrows out of a bow.' There were thirty of them; and as they appear to have been all of one family, it might almost seem as if the greater commonness of this power among the Benjamites arose from its being an hereditary peculiarity of certain families in that tribe. It may also partly have been the result of cultivation; for although the left hand is not naturally an equally strong and ready instrument as the right hand, it may doubtless be often rendered such by early and suitable training.