How to Sign "Swear"
To sign *swear* (meaning to use profanity or curse words), hold your non-dominant hand in front of you with the index finger extended and pointing across your body. Form a 'Y' handshape with your dominant hand by extending your thumb and pinky finger. Strike the palm-side of your dominant 'Y' hand sharply outward against the side of your non-dominant index finger. The dominant hand moves away from your body as it brushes off the stationary finger.