Yes, ruin is a Scrabble word!

Verb

1. Destroy completely; damage irreparably

2. Destroy or cause to fail

3. Reduce to bankruptcy

4. Reduce to ruins

5. Deprive of virginity

6. Fall into ruin

Noun

1. An irrecoverable state of devastation and destruction

2. A ruined building

3. The process of becoming dilapidated

4. An event that results in destruction

5. Failure that results in a loss of position or reputation

6. Destruction achieved by causing something to be wrecked or ruined