adjective
Definition: Relating to a position that is behind or at the rear of something.
Example: The back door is usually quieter than the front one.
intransitive verb
Definition: To move in the opposite direction, especially away from a place or position.
Example: The car backed out of the driveway slowly.
noun
Definition: The rear part of something, often used to provide support or strength, such as the back of a chair or couch.
Example: She leaned against the back of the chair to relax.
transitive verb
Definition: To support or provide evidence for something, to move something in a reverse direction, or to provide backing or reinforcement.
Example: He decided to back the project with additional funding.