Hotness (4)
'hotness' is the definition.
(I know that hotness can be written as heat)
This is the entire clue.
(Other definitions for heat that I've seen before include "Raise temperature" , "Preliminary race to qualify finalists" , "Pressure" , "Hotness" , "Energy that caues a rise in temperature" .)
(Other definitions for temperature that I've seen before include "Degree of heat" , "Degree of hotness" , "Measure of warmth" , "Measure of heat" .)