And a slinger is someone who has a leather pouch with two long cords attached to it, and they put a projectile, either a rock or a lead ball, inside the pouch, and they whirl it around like this and they let one of the cords go, and the effect is to send the projectile forward towards its target.
물매를 쏘는 병사가 두개의 긴 끈이 달린 가죽 주머니에 돌이나 납탄환 같은 발사체를 장착한 뒤 이런 식으로 공중에서 돌리다가 한쪽 끈을 놓으면 발사체가 목표를 향해 날아가게 됩니다.