The word **动弹** (dòngtan) is formed through the combination of two semantically related characters: **动** (dòng), meaning "to move" or "movement," and **弹** (tán), which in this context conveys the idea of "springing" or "bouncing." Together, they create a compound verb that specifically describes a slight, often struggling or hesitant, physical movement, such as wriggling, shifting, or stirring when one's ability to move is limited. This formation follows a common pattern in Chinese where two near-synonymous or complementary morphemes are joined to express a more precise or nuanced action than either character could alone, with the second character often intensifying or specifying the type of motion implied by the first.