Glued (6)
'glued' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for stuck that I've seen before include "Trapped" , "Glued" , "Will's thrust" , "Unable to move" , "Fixed" .)
(Other definitions for gummed that I've seen before include "Covered with glue" , "Stuck, glued" , "Covered with adhesive" .)