To tell someone that they have limited time to do something, or that someone needs to quickly finish up whatever they were already in the middle of. Usually said before something significant is about to happen that would make doing said thing more difficult to do later on.

Assumed to come from the military, with officers letting soldiers know that it was time to rest and indulge (e.g. smoking the cigarettes they earned/found) between movements. However, over time the term has somewhat evolved to imply preparedness and finality, as in "this may be the last time you can do this, so do it now".

Correct speech would be "smoke them if you've got them" which is usually cut down to "smoke 'em if you got 'em" or "smoke 'em if ya got 'em", depending on accent or how fast the phrase is being said.
"Hostiles incoming! Smoke 'em if ya got 'em!"
"Well, I'm the ride home, and I think it's time to go. Smoke 'em if you got 'em, and then I'm leaving - with or without you."
"Please keep your hands and feet inside the vehicle at all times. If at any point during the ride you become disoriented... there's nothing we can do about it. Now, have you removed all of your jewelry...? Are you allergic to shellfish...?" "JEEBS!" "RIGHT THEN! Smoke 'em if ya got 'em!"
by TheRobotMenace March 22, 2022
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Indicates that the smoking tobacco is permissible and encouraged.

Originated in mid-20th century wartime. Commonly used during small gatherings of allied troops. Tobacco was a rationed commodity, at the time, and was generally in short supply.

The term was later popularized in Hollywood war movies.
The commanding officer would typically use the term when opening a meeting in order to get the troops' attention and to relax them (assuming, of course, that they 'had em').

"It's getting rough out there. We've got to review strategy. Smoke 'em if you got 'em. We've got some tough decisions to make...."
by Dave Devoid August 1, 2006
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When there is an unavoidable delay in an activity, some people will say "smoke 'em if you got 'em" as a way of saying "this is going to take a while to fix, so you might as well do something other than just wait (like taking a smoke break)".
After Joe's car broke down on the deserted country road, he called a tow truck and told his passengers "Smoke em if you got em".
by hogarth June 12, 2006
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When in a predicament when it appears there is no escape, one smokes if they have them because the health effects no longer matter.

Said in a time when death is imminent.
As the extinction-level asteroid tumbles toward earth...

John: "I can't believe we're all going to die like this..."
Mark: "Smoke em if you got em, boys. This is it."
John: <lights up>
by BakeCarrots December 30, 2009
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1. In a battle, when both sides have ammo, and lots of em, they just let loose.
2. A fast moving ping pong rally.
3. When an activity is chosen, and its not sure if everyone has the required equipment, the leader yells smoke em if you got em, and the activity commences
by dildo monger June 2, 2004
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