The antonyms for the word "defeatable" are invincible, unstoppable, unbeatable, indestructible, and unconquerable. The word "invincible" means incapable of being defeated, unbeatable, or unconquerable. "Unstoppable" means impossible to stop or prevent, while "unbeatable" means not capable of being defeated. "Indestructible" refers to something that can't be destroyed or ruined, and "unconquerable" means impossible to overcome or defeat.
These antonyms are frequently used to express the idea of strength, power, and resilience. These words can be used to describe a person, an object, or a situation that is difficult to overcome or defeat.