their sign in american sign language (asl) represents belonging to or associated with something previously mentioned or easily identified. This sign is non-gendered and is typically used as a substitute for the word "their" in everyday conversation. Like the signs for "her" or "him," the sign for "their" is shaped like a capital "H" with the top and bottom arms extended. The fingers of the hand are also shaped into a fist, and the palm faces forward.
In terms of usage, the sign their is used to indicate possession of an object or item by the person or people mentioned. For example, if someone has "their dog" in their home, they could sign "their dog" with a "b" palm facing forward to show that the dog belongs to them. Similarly, if a friend gives them a gift, they could sign "their gift" with the same gesture.
It is important to note that the sign their is not commonly used to indicate possession in the sense of ownership in ASL. Instead, possession is often indicated by using the word "have" with the sign for the possessor's handshape, which is typically a "b" palm facing forward. For example, if someone has "my book," they could sign it by placing their fingertips on their chest with a "b" palm faced forward.
Overall, the sign their in asl serves to convey the idea of belonging to or association with something, and is typically used in the context of everyday conversation to articulate possession. It is important to note that the sign is non-gendered and can be used by anyone, regardless of gender.