The word 要挟 is formed by combining the character 要, which here means "to demand" or "to seek", with 挟, meaning "to clasp under the arm" or "to exert pressure". Together, they create a compound verb where 要 emphasizes the act of demanding, and 挟 adds the notion of holding or forcing, resulting in the meaning "to coerce" or "to blackmail" through the use of threats or pressure.