Threatening words worried lessee? There's nothing odd in that (2,4)
I believe the answer is:
or else
'threatening words' is the definition.
(do what I say... or else!)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for or else that I've seen before include "Statement that threatens" , "Instead of" , "Otherwise - that's a threat" , "Alternatively" , "Otherwise - may be threatening" .)