Caught by dreadful threat or idle talk (7)
I believe the answer is:
chatter
'idle talk' is the definition.
(I've seen this before)
'caught by dreadful threat' is the wordplay.
'caught' becomes 'c' (cricket abbreviation).
'by' says to put letters next to each other.
'dreadful' indicates an anagram.
'threat' anagrammed gives 'hatter'.
'c'+'hatter'='CHATTER'
'or' acts as a link.
(Other definitions for chatter that I've seen before include "Talk incessantly" , "Speak rapidly and incessantly" , "Idle gossip" , "Small talk" , "Talk noisily" .)