See usage in Webster's New World College Dictionary
noun
the act, way, or extent of using or treating; treatment; use
long-continued or established practice; habitual or customary use or way of acting; custom; habit
the way in which a word, phrase, etc. is used to express a particular idea; customary manner of using the words of a given language in speaking or writing, or an instance of this
See usage in American Heritage Dictionary 4
(yo͞oˈsĭj, -zĭj)
noun
a. The act, manner, or amount of using; use: the usage of a technical term; an instrument that measures water usage.
b. The act or manner of treating; treatment: subjected the car to rough usage.
A usual, habitual, or accepted practice. See Synonyms at habit.
The way in which words or phrases are actually used, spoken, or written in a speech community.
A particular expression in speech or writing: a nonce usage.