Boilers lubricant (3)
I believe the answer is:
oil
'lubricant' is the definition.
(I've seen this in another clue)
'boilers' is the wordplay.
'OIL' is hidden in amongst the letters.
However, I am not sure how the hidden word is indicated.
Can you help me to learn more?
(Other definitions for oil that I've seen before include "SECOND PART OF 23" , "Valuable viscous liquid" , "what can be seen on iceberg" , "eg Olive" , "Liquid fuel" .)