A heriditary disorder that causes dwarfism. The word means "Absence of cartilage growth" in greek, and achondroplasia is a condition where the cartilage on long bones (limbs especially, but it also affects the base of the skull) fails to grow. Achondroplastic dwarfs (many circus dwarfs have this condition) have a normal sized trunk and head, with a slightly protruding forehead, and very short (but very strong - muscle growth is not affected) arms and legs.