NCI Dictionary of Cancer Terms

The NCI Dictionary of Cancer Terms features 8,612 terms related to cancer and medicine.

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A chemical substance that kills sperm and is used as a type of birth control. It is available over-the-counter (without a doctor’s order) and comes in many different forms such as cream, gel, foam, and suppository. Spermicides can be used alone or with another birth control method such as a condom or diaphragm. They do not protect against sexually transmitted diseases (STDs).