A dour disposition is, to us, hard to bear (7)

I believe the answer is:

arduous

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

'hard to bear' is the definition.
I can't judge whether this definition defines the answer.

'a dour disposition is to us' is the wordplay.
'disposition' is an anagram indicator.
'is to us' becomes 'us'.
'dour' with letters rearranged gives 'rduo'.
'a'+'rduo'+'us'='ARDUOUS'

Can you help me to learn more?

(Other definitions for arduous that I've seen before include "Steep; laborious" , "Requiring great effort" , "Difficult, tiring" , "Burdensome" , "Toilsome" .)

I've seen this clue in The Irish Independent.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.