Say senseless crook close to treasure — is it seen in large chest? (8)
I believe the answer is:
silicone
'chest?' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'say senseless crook close to treasure is it seen in large' is the wordplay.
I cannot really understand how this works, but
'crook' could be 'con' and 'con' is present in the answer.
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is present in the answer.
'large' could be 'l' (eg in clothes sizes) and 'l' is found within the answer.
'is' could be 'ii' (more than one I) and 'ii' is found within the remaining letters.
A single letter 's' remains 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 silicone that I've seen before include "Polymer used in paints and implants, say" , "It's used in, say, synthetic rubber" , "Body implant resin" , "What's used in breast implants" , "Synthetic compound" .)