jack-in-the-box /ˈʤækənðəˌbɑːks/ noun plural jack-in-the-boxes or jacks-in-the-box
plural jack-in-the-boxes or jacks-in-the-box
Learner's definition of JACK-IN-THE-BOX
[count]
: a toy that is a small box containing a clown or other figure which jumps up when the box is opened玩偶匣(揭开匣盖时玩偶自行跳起)