I have always found the term "Glib" somewhat confusing:
Glib\, n. [Ir. & Gael. glib a lock of hair.] A thick lock of hair, hanging over the eyes. [Obs.]
"The Irish have, from the Scythians, mantles and long glibs, which is a thick curied bush of hair hanging down over their eyes, and monstrously disguising them." --Spenser.
"Their wild costume of the glib and mantle." --Southey.
Webster's Revised Unabridged Dictionary, © 1996, 1998 MICRA, Inc."
The OED says, "A thick mass of matted hair on the forehead and over the eyes, formerly worn by the Irish."
My modern Irish/English dictionary translates glib as "Fringe".
Irenius attacks the glib, the Irishman's long hair, like a woman's, which enables him to disguise himself whether he covers his face with his hair or cuts the hair off.
"A ‘glib’ was a thick roll of hair at the forehead which a law of 1537 specifically forbade the English in Ireland to wear." (Nothing is in the Statutes of Kilkenny that I could find).
From these definitions it sounds that it could also be long hair hanging in locks. If you look at the Derricke woodcut of, "Turlough Lynagh O'Neale and the other kerne kneel to Sidney in submission." The Kern's hair is long and hanging in locks all around the head, not just the front. http://www.lib.ed.ac.uk/about/bgallery/ ... 64_jpg.htm
I'm just throwing this out as another posible interpretation, as opposed to the Kern in Durer's print. I'm really not sure, but it could even be both.