zizz /zɪz 
/ informal mainly British English ▸ noun [in singular] 1 a whizzing or buzzing sound: the metallic zizz of the starter motor.
2 a short sleep: Angus was in his basket having a zizz.
▸ verb [no object] 1 make a whizzing or buzzing sound: the banger started zizzing furiously.
2 doze; sleep: Louise zizzed most of the time, stretched out on a sofa.
– ORIGIN early 19th century: imitative.
EnglishOxford Dictionary of English
