Definition of "rekern"

Illustrator tends to treat a line of text as an object, so changing a word at the end of a line can often result in a great deal of hand-manipulation to rekern the type or move a word onto the next line.

1996, Bruce Page, Diana Holm, Web Publishing with Adobe Acrobat and PDF, page 227

Here the original drawing is shown in grey and the infilled tracing in black. The lettering can be further refined and, unlike ink-based artwork, can be rekerned without being redrawn.

2011, Andrew Haslam, Lettering: A Reference Manual of Techniques