plural jacks
Definition of jack
(Entry 1 of 2)
1a jacks plural in form but singular in construction : a game played with a set of small objects that are tossed, caught, and moved in various figures
b : a small 6-pointed metal object used in the game of jacks
2a : a playing card carrying the figure of a soldier or servant and ranking usually below the queen
3 : any of various usually mechanical devices: such as
a : a usually portable mechanism or device for exerting pressure or lifting a heavy body a short distance
b : a device for turning a spit
4 : a female fitting in an electric circuit used with a plug to make a connection with another circuit
6 : something that supports or holds in position: such as
a : an iron bar at a topgallant masthead to support a royal mast and spread the royal shrouds
b : a wooden brace fastened behind a scenic unit in a stage set to prop it up
7a : any of several fishes especially : any of various carangids
b : a male donkey
c : jackrabbit
d : any of several birds (such as a jackdaw)
8a : a small white target ball in lawn bowling
b : a small national flag flown by a ship
11 : jackknife sense 2
12 : monterey jack
13 US slang : anything at all
—used in negative constructionsIn short, Dinger or Homer or whoever it was who wrote the Odyssey didn't know jack about travel.— Steve Rushin
jack
verbjacked; jacking; jacks
Definition of jack (Entry 2 of 2)
1a : to move or lift by or as if by a jack
b : to raise the level of
—usually used with upjack up the price
c : to take to task
2 : to hunt or fish for at night with a jacklight
: to hunt or fish at night with a jacklight
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Time Traveler for jack
The first known use of jack was in 1548
See more words from the same year