Flash German fabric (5)
I believe the answer is:
glint
'flash' is the definition.
(glint is a kind of flash)
'german fabric' is the wordplay.
'german' becomes 'g' (abbreviation).
'fabric' becomes 'lint' (lint is a kind of fabric).
'g'+'lint'='GLINT'
(Other definitions for glint that I've seen before include "Flash of light (in the eye?)" , "Bright, brief gleam" , "Momentary flash of light" , "Brief indication" , "Give out small flashes of light" .)