1. (noun) the protruding part of the lower jaw

• chin

1. (noun) a projection like a chin formed by the sepals and base of the column in some orchids

• plant part
• plant structure

2. (noun) the protruding part of the lower jaw

• feature
• lineament

3. (noun) a projection below the mouth of certain mollusks that resembles a chin

• body part

1. (noun) the protruding part of the lower jaw

• buccula
• double chin