To help a child between 8 and 14 months old stop biting:
Make clear rules about biting. Tell the child, “We never bite people. We bite food like apples and cookies.”
If the child bites, say “Biting hurts.” If you are bitten, exaggerate your response to the pain. This helps the child learn why you are upset when he or she bites.
Use a stern voice and wear a stern expression on your face as you talk about biting. Babies of this age may not understand your words, but they can understand your body language, facial expression, and tone of voice.