paroxysm
Pronunciation: /ˈparəksɪz(ə)m/
noun

Origin:
late Middle English: from French paroxysme, via medieval Latin from Greek paroxusmos, from paroxunein 'exasperate', from para- 'beyond' + oxunein 'sharpen' (from oxus 'sharp')

Spelling help
Remember that paroxysm ends with -ysm.