American put in a lot of money to produce Chambers (7)
I believe the answer is:
cameras
'produce chambers' is the definition.
The answer and definition can be both man-made objects as well as being plural nouns.
Perhaps you can see an association between them that I can't see?
'american put in a lot of money' is the wordplay.
'american' becomes 'amer' (rare abbreviation).
'put in' means one lot of letters goes inside another.
'a lot of money' becomes 'cas' (I can't justify this - if you can you should believe this answer much more).
'amer' placed inside 'cas' is 'CAMERAS'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for cameras that I've seen before include "television equipment" , "Image recorders" , "Light-proof boxes" .)