Definitions for "Galley proof"
Any proof taken of type matter while it is still on the galley.
Proofs taken from the galleys before being made up into pages. The phrase is still sometimes used to refer to early proofs, although most print no longer uses hot metal setting.
Copies of the book (usually in an inexpensive binding) intended for the author, editors, and proof readers to correct.
Keywords:  ghosting, gloss
Ghosting Gloss