The spelling of the word "clubb" can be confusing, as it contains a double B. However, this is because the word is derived from the Old English word "clibban," which also contained a doubled consonant. To represent this sound in modern spelling, the word uses the letter "b" twice. Its phonetic transcription is /klʌb/ indicating that the first "b" sound can be said aspirated with a short vowel sound. "cluh" while the second "b" should be pronounced as a plosive /b/ sound with a short vowel /ʌ/ after it.
The word "club" derives from the Old Norse word "klubba", which referred to a heavy stick or cudgel used as a weapon. This Norse term was borrowed into Middle English as "clun", which evolved into "club" in modern English. The etymology of "klubba" is uncertain, but it is thought to possibly be onomatopoeic, imitating the sound made when striking something with a heavy object.