* Deaf as a cultural identity: If you're referring to the Deaf community as a cultural group with its own language, values, and history, the sign is "Deaf" with the "D" handshape and a movement that goes from the chin to the chest. This is a capitalized "Deaf" to distinguish it from the medical term.
* Deaf as a medical condition: If you're talking about deafness as a hearing impairment, the sign is "hearing impaired" or "hard of hearing" depending on the degree of hearing loss.
* Deaf as an adjective: If you're using "deaf" to describe someone who can't hear, you'll need to use a sign that incorporates the context, like "He is deaf" or "She is deaf."
It's important to be sensitive and respectful of the Deaf community and their preferred language. Always use the terminology that reflects their own self-identification and understanding.