Rasta left traumatised by boredom (6)

I believe the answer is:

tedium

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

'boredom' is the definition.
('tedium' can be a synonym of 'boredom')

I don't understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for tedium that I've seen before include "State of being bored" , "Boredom, tiresomeness" , "Banality" , "Boredom, mental weariness" , "'Boredom, ennui (6)'" .)

I've seen this clue in the Irish Times and the Irish Times (Crosaire).

Want a hint initially instead of a full solution? Install my app