revel
Pronunciation: /ˈrɛv(ə)l/
verb ( revels, revelling, revelled; US revels, reveling, reveled)

Origin:
late Middle English: from Old French reveler 'rise up in rebellion', from Latin rebellare 'to rebel'

Spelling rule
Double the l when adding endings which begin with a vowel to words which end in a vowel plus l (as in travel):