snorkel
Pronunciation: /ˈsnɔːk(ə)l/
noun
verb ( snorkels, snorkelling, snorkelled; US snorkels, snorkeling, snorkeled)

Origin:
1940s: from German Schnorchel

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):