Rollerball

Part of speech: noun

Definitions

1. A writing instrument that uses a gel or liquid ink released by a ball point
2. A type of pen that enhances smoothness and fluidity in writing through a rotating ball
3. A refillable pen designed for ease of use and vibrant ink application

Etymology: "Rollerball" is a plain compound of "roller" and "ball," and its history is as literal as the name suggests. A rollerball pen puts a small metal ball at the tip of a tube of liquid or gel ink; as the pen moves across paper, the ball turns and carries a thin, steady layer of ink onto the surface. The name describes the mechanism exactly: the ball rolls, and the ink rolls out with it. The "roller" half comes from the verb "roll," which in English has long meant to move by turning over and over on an axis, and "ball" is an ordinary round object. Put together, the compound names the rolling ball itself, and the pen takes its name from the component that does the work rather than from anything about writing.