Get lidless, brandless boxes full of beans (9)
I believe the answer is:
energetic
'full of beans' is the definition.
(I've seen this before)
'get lidless brandless boxes' is the wordplay.
'lidless' means to remove the first letter.
'brandless' becomes 'energic' (I can't explain this - if you can you should believe this answer much more).
'boxes' means one lot of letters goes inside another (the outside letters must 'box' inside letters in).
'get' with its initial letter taken off is 'et'.
'et' going into 'energic' is 'ENERGETIC'.
Can you help me to learn more?
(Other definitions for energetic that I've seen before include "Forceful, vigorous" , "Lively, spirited" , "High-powered" , "Forceful and with great vitality" , "Vigorous and dynamic" .)