A lot of lake and brown cloth (6)
I believe the answer is:
tartan
'cloth' is the definition.
(tartan is a kind of cloth)
'a lot of lake and brown' is the wordplay.
'a lot of' means to remove the last letter (most of the word but not all of it).
'lake' becomes 'tarn' (tarn is a kind of lake).
'and' means one lot of letters go next to another.
'brown' becomes 'tan' (tan is a kind of brown).
'tarn' with its final letter removed is 'tar'.
'tar'+'tan'='TARTAN'
(Other definitions for tartan that I've seen before include "Scots patterned cloth" , "Pattern of the Scottish clans" , "Clan fabric" , "chequered cloth" , "Woollen fabric with plaid design" .)