Kerning

n. (in typography) technique of setting a pair of letters closer together than is usual by reducing the space between them, tracking

v. produce kernels or grains; granulate (esp. salt); cover with salt; adjust spacing between two letters (DTP, Printing)

In typography, kerning, or less commonly, mortising (referring to the process of physically removing material from the cast character), is the process of adjusting letter spacing in a proportional font. In a well-kerned font, the two-dimensional blank spaces between each pair of letters all have similar area.
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n. (in typography) technique of setting a pair of letters closer together than is usual by reducing, tracking

(p. pr. & vb. n.)
of Kern
  

<text> The process of reducing the spacing between certain pairs of letters to improve their appearance. When a font is created, each character is given a width that includes some space around it so that the letters don't run into each other when displayed or printed. This can be thought of as an invisible box around each character. Some pairs of characters such as A and V, look better if the boxes overlap slightly, bringing the characters closer together (but still not touching).
See also tracking, leading.
(1996-06-07)