Crossword Genius

Folk star's alarming words (7)

Ross

I believe the answer is:

menaces

Here is my best explanation:

'alarming words' is the definition.
('menaces' can mean threatening words)

'folk star's' is the wordplay.
'folk' becomes 'men' (I've seen this in other clues).
'star's' becomes 'aces' ('ace' can be a synonym of 'star').
'men'+'aces'='MENACES'