Bring in wimpy forts without walls (6)
I believe the answer is:
import
'bring in' is the definition.
(I've seen this before)
'wimpy forts without walls' is the wordplay.
'wimpy' becomes 'imp' (I can't justify this - if you can you should give a lot more credence to this answer).
'without walls' indicates the central letters (the letters on the edges are removed).
The centre of 'forts' is 'ort'.
'imp'+'ort'='IMPORT'
Can you help me to learn more?
(Other definitions for import that I've seen before include "Implied meaning, bring from abroad" , "Convey" , "introduce" , "introduction" , "Meaning - something from abroad" .)