feather edge

noun, verb — 2 senses

noun

An edge of a board, plank, etc. that has been made very thin.

verb

To give a very thin edge to.

Featheredging is a process in preparing the photographs for mosaicking and involves cutting, tearing, and sandpapering the back of the print along its edges in such a way that the edge of the print is thin and will make a smooth match with adjoining prints.1944, War Department Technical Manual, volume 5, number 240, page 60:

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