Big lama ruined letter holder (7)
I believe the answer is:
mailbag
'letter holder' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'big lama ruined' is the wordplay.
'ruined' is an anagram indicator.
'big'+'lama'='biglama'
'biglama' with letters rearranged gives 'MAILBAG'.
Can you help me to learn more?
(Other definitions for mailbag that I've seen before include "Postal sack" , "Container for carrying letters" , "carrier" , "One sewn by convicts" , "Sent down sewer's product" .)