Used in the Phillipines and by the U.S. Army. Origin: Phillipine Spanish, 1900 >- 1905.
The successor to the Main Battle Tank which was limited to Direct Fire in the Close Support Role. The Bolo was developed with the upgrading of the Indirect Fire, Active Protection, Electronic and Cyber-Warfare capabilities to that same "Close Support" role. The main battle tank fulfills the role the British had once called the 'universal tank', filling almost all ground battlefield roles. The Bolo fulfills ALL ground battlefield roles.
-Bolo_original_definitions
Heavily adapted from these Wiki's- Bolo (tank), Chain shot, Shotgun, Bolas
Prior to the Mark XIV, early Bolo Marks utilized projectile weapons for their main battery. All marks of Bolos are equipped with a set of secondary batteries such as rapid-fire mortars and heavy howitzers. In artillery, a chain-shot is an obsolete type of naval ammunition formed of two sub-caliber balls, or half-balls, chained together. They were used in naval warfare in the age of sailing ships and black powder cannons to shoot masts, or to cut the shrouds and any other rigging of a target ship. In modern times, the effect is replicated in shotguns with the use of bolo shells, consisting of two slugs joined by steel wire. When fired, the slugs stretch the connecting wire, causing it to slice up its target badly when it hits. They are banned in several jurisdictions, including Florida and Illinois.

A Bolas is a throwing weapon. IMO, where the B-18 (long range bomber) got its name from. (bola being Spanish for 'ball', is also the etymology of Bolo ties)
myetymology.com:
The Greek suffix -bolos, -βολος, -βόλος
derived from the Greek word ballein, βάλλω (to throw)