Where does “τζίτζικας” come from?

τζίτζικας (Byzantine Greek) comes from Ancient Greek τέττιξ, from Ancient Greek τιτίζω.

Ancestry of “τζίτζικας”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	τέττιξ	cicada; a gold ornament worn in the hair,...
2	Ancient Greek	τιτίζω	—

τζίτζικας — Etymology, Origin & Word History | Etymology Explorer