Grand made a tidy sum kept at home (8)
I believe the answer is:
grounded
'kept at home' is the definition.
The definition and answer can be both related to thinking as well as being past participle verbs.
Perhaps there's a link between them I don't understand?
'grand made a tidy sum' is the wordplay.
I cannot quite see how this works, but
'grand' could be 'g' (G is short for grand as in a thousand) and 'g' is found within the answer.
The remaining letters 'rounded' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for grounded that I've seen before include "prevented from leaving home" , "Not allowed to fly" , "Earthed" , "Prevented from flying" , "Based; forbidden to fly" .)