Crossword Genius

Cover coolants regularly going missing (4)

Ross

I believe the answer is:

coat

Here is my best explanation:

'cover' is the definition.
(coat is a kind of cover)

'coolants regularly going missing' is the wordplay.
'regularly going missing' indicates alternate letters.
The alternating letters of 'coolants' are 'COAT'.

This clue was last seen in The Times