retouch

To improve something (especially a photograph), by adding or correcting details, or by removing flaws.

For time ſhall with his ready pencil ſtand; Retouch your figures with his ripening hand; Mellow your colors, and imbrown the teint; Add every grace, which time alone can grant; To future ages ſhall your fame convey, And give more beauties than he takes away.

To colour the roots of hair to match hair previously coloured.

To modify a flint tool by making secondary flaking along the cutting edge.

The act of retouching.