Year 410 (CDX) was a common year starting on Saturday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year after the Consulship of Honorius and Theodosius (or, less frequently, year 1163 Ab urbe condita). The denomination 410 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.

.410 bore, commonly incorrectly named the .410 gauge, is the smallest gauge of shotgun shell commonly available. It has similar base dimensions to the .45 Colt revolver cartridge, though the .410 is significantly longer, up to , allowing many single-shot firearms and some revolvers chambered in that caliber to fire shot without any modifications.