look up any word, like tribbing:
 
2.
Grenade launcher, found in Call of Duty 4: Modern Warfare
"That kid just shot me with his newb tube!"
by Bojay Blues June 21, 2008
 
1.
A granade launcher in Call Of Duty 4 and WAW. Which takes no skill to use so people that are new to the game or just not good at it use.
That newb shot me with his newb tube
by cagrown760 March 27, 2009
 
3.
The Newbtube is a nickname for the Gernade Launcher attachment in the Call of Duty series. It is named that because newbies tend to use it as their only way to get kills, because it will kill their opponents in one shot.
I'm playing like crap, I'll use the Newbtube to get some quick kills.
by Fitty4ex May 22, 2008