Final answer:
Relative timing is considered an invariant feature of movement, referring to a characteristic that remains constant across different instances such as the sequence in which movement phases occur in methods like archaeology and geology.
Step-by-step explanation:
The term relative timing is typically associated with methods used in various fields such as archaeology, geology, and history to determine the relative order of past events. This concept involves comparing two or more artifacts or layers of sediment to establish which one is older based on their positions or contexts relative to each other. This technique does not provide an absolute age but can accurately outline the sequence of events or the age of objects relative to each other.
In the context of the question, relative timing is considered a(n) invariant feature of movement, as it refers to a characteristic that remains constant across different instances of an action or event, such as the sequence in which movement phases occur.