Current carrying resistance gets hot (8)
I believe the answer is:
tropical
'hot' is the definition.
(similar in meaning)
'current carrying resistance gets' is the wordplay.
'current' becomes 'topical' (similar in meaning).
'carrying resistance' becomes 'r' (I can't explain this - if you can you should give a lot more credence to this answer).
'gets' is an insertion indicator.
'topical' placed around 'r' is 'TROPICAL'.
Can you help me to learn more?
(Other definitions for tropical that I've seen before include "Of regions north and south of the Equator" , "Hot and humid, as north and south of the equator" , "Originating from hotter parts of the earth" , "Describes weather that is hot and humid" , "Belonging to hot regions" .)