Military pageant — rubbish as well! (6)
I believe the answer is:
tattoo
'military pageant' is the definition.
(I've seen this before)
'rubbish as well' is the wordplay.
'rubbish' becomes 'tat' (low-quality items or material).
'as well' becomes 'too' (both can mean 'also').
'tat'+'too'='TATTOO'
(Other definitions for tattoo that I've seen before include "Military display - needlework!" , "Drum signal, display" , "personal adornment?" , "display involving military band" , "Military evening signal" .)