Pet (noun)

1. A domesticated animal kept for companionship or pleasure.
2. An object of one's attention or affection.

Origin:

Late 16th century: from latin petere "to go to, seek".

Examples:

1. She has a dog for a pet.
2. The cat is her favorite pet.
3. He has a pet rock.
4. The rabbit is a cute pet.
5. She spends a lot of time with her pet parrot.