Crossword Genius

Sheet a fathead gets oil on (4)

Ross

I believe the answer is:

foil

I'm a little stuck... Click here to teach me more about this clue!

'sheet a fathead' is the definition.
'foil' can be an answer for 'sheet' (thesaurus). I am not certain of the 'a fathead' bit.

'gets oil on' is the wordplay.
'gets' becomes 'f' (I am not sure about this - if you are sure you should believe this answer much more).
'on' means one lot of letters go next to another.
'f'+'oil'='FOIL'

Can you help me to learn more?

(Other definitions for foil that I've seen before include "Thin metal sheet; frustrate" , "Prevent from succeeding" , "Frustrate - sheet - rapier" , "metal used in > sword" , "Prevent the success of; fencing sword" .)

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