A repeating firearm or repeater is any firearm that is capable of being fired repeatedly before having to be manually reloaded with new ammunition into the firearm.
Colt Holster Model Paterson Revolver No. 5
Circuit Judge revolver mechanism carbine
Replica Puckle gun from Buckler's Hard Maritime Museum
Confederate revolving cannon
In firearm designs, the term single-shot refers to guns that can hold only a single round of ammunition inside and thus must be reloaded manually after every shot. Compared to multi-shot repeating firearms ("repeaters"), single-shot designs have no moving parts other than the trigger, hammer/firing pin or frizzen, and therefore do not need a sizable receiver behind the barrel to accommodate a moving action, making them far less complex and more robust than revolvers or magazine/belt-fed firearms, but also with much slower rates of fire.
Shiloh Sharps Model 1874 Hartford in .50-90 Sharps
Open action of Cooper Model 22 single-shot rifle