Clear material picked up in accordance with plans (7)
I believe the answer is:
perspex
'clear material picked up' is the definition.
I can't tell whether this defines the answer.
'in accordance with plans' is the wordplay.
'in accordance with' becomes 'per' (I've seen this in another clue).
'plans' becomes 'spex' (I can't explain this - if you can you should believe this answer much more).
'per'+'spex'='PERSPEX'
Can you help me to learn more?
(Other definitions for perspex that I've seen before include "Tough transparent lightweight plastic" , "Solid transparent plastic" , "Transparent thermoplastic acrylic resin" .)