Cold house showing signs of decay (6)
I believe the answer is:
caries
'decay' is the definition.
(dental caries)
'cold house showing signs' is the wordplay.
I cannot quite understand how this works, but
'cold' could be 'c' (eg on taps) and 'c' is found in the answer.
'house' could be 'aries' (Aries is an example) and 'aries' is found within the answer.
This accounts for all the letters.
This explanation may well be incorrect...
'of' acts as a link.
Can you help me to learn more?
(Other definitions for caries that I've seen before include "Decayed area in a tooth" , "Decay of bone or teeth" , "Decayed areas in teeth" , "Decay in bones or teeth (6)" , "Dental cavities" .)