Heel (noun)

1. The back part of a foot below the ankle, on which a person stands or walks.
2. The lower end of a shoe or sock that covers the heel of the foot.
3. A contemptible or unreliable person.
4. A tool used to cut or shape the heel of a shoe or boot.

Origin:

Middle english: from old norse hæl, of germanic origin; related to dutch hiel and german ferse.

Examples:

1. She hurt her heel while playing tennis.
2. He bought new shoes with comfortable heels.
3. The heel of the shoe was worn down.
4. Don't trust him, he's a real heel.
5. The cobbler used a heel tapping machine to reinforce the heel of the shoe.