Act of dominion

What does Act of dominion mean in American Law?

The definition of Act of dominion in the law of the United States, as defined by the lexicographer Arthur Leff in his legal dictionary is:

An act by which a person evinces his taking dominion, i.e., ownership, of a thing, e.g., accepting a deed to real property in modern practice, or in older practice accepting a twig while standing on the land being conveyed. But acts of dominion need be neither formal nor dramatic; driving a new car away from the showroom and eating an ice cream cone are also acts of dominion.