Variant

Unlike alternate dimensions, alternate timelines are all variations of similar starting points. This means that similar characters exist across timelines, with varying differences. A variant is the term used to describe a version of a character from a different timeline. 
Prime variant is the term used to describe the original or most prominent variant of a character.
For example, see the prime variant Bogus Comogus and his variant from the Bogus Comogus extended series, Bogus Comogus (variant 4).
For the dimensional version of this term, see equivalent.