Risky (adjective)

1. Involving a level of danger or chance of failure.
2. Involving a chance of loss or injury.
3. Likely to result in a negative outcome.
4. Uncertain as to outcome.

Origin:

Late 19th century: from risk + -y.

Examples:

1. The investment was risky.
2. The plan was too risky to implement.
3. The situation was risky.
4. The stock market is a risky business.
5. The operation was risky but successful.