BB gun

(from the article `air gun`) Most modern air guns are inexpensive BB guns (named for the size of the shot fired). The best of these develop about half the muzzle velocity of ...
Found on http://www.britannica.com/eb/a-z/b/35

BB gun

[n] - an air gun in which pellets are propelled by air pressure
Found on http://www.webdictionary.co.uk/definition.php?query=BB%20gun

BB gun

noun an air gun in which BBs are propelled by compressed air
Found on http://wordnetweb.princeton.edu/perl/webwn?s=BB%20gun
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