Heat source from brazier if nobody up? (7)
I believe the answer is:
bonfire
'heat source' is the definition.
'bonfire' can be an answer for 'source' (I have seen 'Source of blazing' mean 'bonfire' so perhaps 'source' could also mean 'bonfire'). I am not certain of the 'heat' bit.
'from brazier if nobody up?' is the wordplay.
'from' indicates the answer is hidden within the clue.
'up?' says the letters should be written in reverse (in down clue: letters go upwards).
'erifnob' is hidden in the letters of 'brazier if nobody'.
'erifnob' reversed gives 'BONFIRE'.
Can you help me to learn more?
(Other definitions for bonfire that I've seen before include "Means of waste disposal, perhaps" , "If Ron be outside, is he alight?" , "Signal" , "No brief for an open air conflagration" , "It is lit to celebrate Guy Fawkes's day" .)