Body artist first to support military pageant (9)
I believe the answer is:
tattooist
'body artist' is the definition.
'tattooist' can be an answer for 'artist' (I've seen this before). I'm unsure of the 'body' bit.
'first to support military pageant' is the wordplay.
'first to' becomes 'ist' (I've seen this in other clues).
'support' means one lot of letters go next to another (in a down clue, some letters hold others up).
'military pageant' becomes 'tattoo' (I've seen this before).
'ist' after 'tattoo' is 'TATTOOIST'.
Can you help me to learn more?
(Other definitions for tattooist that I've seen before include "Designer" , "Skin artist" , "permanent marker?" , "Skin decorator" , "Sort of marksman" .)