ˈ ̷ ̷ ̷ ̷ ̷ ̷ˌ ̷ ̷ noun
( plural jack-in-the-boxes also jacks-in-the-box )
Usage: sometimes capitalized J
1. obsolete : sharper , cheat
2. : a child's toy consisting of a box out of which a figure springs when the lid is raised
3. : any of several mechanical contrivances: as
a. : differential gear
b. : a large wooden screw turning in a nut attached to the crosspiece of a rude press
c. : a lifting jack : jackscrew
d. : a burglar's tool for opening doors or safes by means of a small but powerful screw
e. : a jim-crow reversing tool
f. : sun-and-planet motion