The Correct spelling is: occur
Common misspellings of the word occur are:
How do you spell occur?. It is not occour or occurr or even ocurr for that matter!
intr.v., -curred, -curÂ·ring, -curs.
- To take place; come about. See synonyms at happen.
- To be found to exist or appear: Copper deposits occur in the region.
- To come to mind: The idea never occurred to me.
[Latin occurrere : ob-, toward; see obâ€“ + currere, to run.]