Glittering, like part of American flag (8)
I believe the answer is:
spangled
I believe this is a double definition.
'glittering' is the first definition.
(I've seen this in another clue)
'like part of american flag' is the second definition.
(the US flag is called the star-spangled banner)
(Other definitions for spangled that I've seen before include "Glitteringly decorated" , "Decorated with shiny spots (as is the US flag)" , "Glittery" , "Flag of USA is the Star-. . . . . . . . Banner" .)