Yes, spare is a Scrabble word!

Verb

1. Refrain from harming

2. Save or relieve from an experience or action

3. Give up what is not strictly needed

4. Use frugally or carefully

Adjective

1. Thin and fit

2. More than is needed, desired, or required

3. Not taken up by scheduled activities

4. Kept in reserve especially for emergency use

5. Lacking in amplitude or quantity

6. Lacking embellishment or ornamentation

Noun

1. An extra component of a machine or other apparatus

2. An extra car wheel and tire for a four-wheel vehicle

3. A score in tenpins; knocking down all ten after rolling two balls