A word used during role play and BDSM to immediately end the activity.

By choosing a safe word, the submissive partner is able to take on his or her role completely, saying words like “no” or “stop” without actually compelling the dominant partner to stop. Safe words are often unusual words or phrases, as this allows for an unambiguous signal – the safe word isn’t likely to come up naturally, so when the dominant partner hears it, he or she knows to stop.