Used to form words to describe people who are dedicated fans of something, especially music.
Used to create nouns indicating a state; -hood.
Used to form words for people who regularly have their mind focused upon a particular subject, activity, or a specified drug or other substance, or who are addicted in some way.
Used with other words to form generic insults or epithets to indicate stupidity.
One who uses or makes use of something, a consumer/client or an express or implied licensee (free user) or a trespasser.
A person who uses drugs, especially illegal drugs.
A person who uses a computer or a computing network, especially a person who has received a user account.
An exploiter, an abuser (a person who "uses" people, that is treats and regards people unfairly, selfishly and/or unethically).