"ballpoint (pen)." YourDictionary, n.d. Web. 14 September 2018. <http://www.yourdictionary.com/ballpoint-pen>.
ballpoint (pen). (n.d.). Retrieved September 14th, 2018, from http://www.yourdictionary.com/ballpoint-pen
(plural ballpoint pens)
A pen, similar in size and shape to a pencil, having an internal chamber filled with a viscous, quick-drying ink that is dispensed at the tip during use by the rolling action of a metal sphere (around 0.7 mm to 1 mm in diameter).
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