Noun
A small lead or steel shot, or ammunition, used in shotgun shells.
A rifle or pistol cartridge containing small shot instead of a single larger projectile.
Source: en.wiktionary.orgLike birdshot, buckshot is described by pellet size, with larger numbers indicating smaller shot. Source: Internet
Shot is termed either birdshot or buckshot depending on the shot size. Source: Internet
Shotshell reloading for specialty purposes, such as for buckshot or slugs, or other specialty rounds, is often practiced, but varies significantly from the process steps discussed previously for handloading birdshot shotshells. Source: Internet
Buckshot is similar to but larger than birdshot, and was originally designed for hunting larger game, such as deer (hence the name). Source: Internet
Of this general class, the most common subset is birdshot, which uses a large number (from dozens to hundreds) of small pellets, meant to create a wide "kill spread" to hunt birds in flight. Source: Internet