Retro samovar boils inside creating cheer (5)
I believe the answer is:
bravo
'cheer' is the definition.
(I know that bravo is a type of cheer)
'retro samovar boils inside' is the wordplay.
'retro' says the letters should be written in reverse (retro is Latin for 'backwards').
'inside' says the answer is hidden in the clue.
'ovarb' can be found hidden inside 'samovar boils'.
'ovarb' backwards is 'BRAVO'.
'creating' acts as a link.
(Other definitions for bravo that I've seen before include "Radio code word for B" , "How broadcaster might begin birthday" , "B in radio communications" , "Well done; B (radio)" , "Cry of approval" .)