Where does “σφιγκτῶς” come from?

σφιγκτῶς (Ancient Greek) comes from Ancient Greek σφιγκτός, from Ancient Greek -τός, from Proto-Indo-European -tós — Creates verbal adjectives from verb stems.

Ancestry of “σφιγκτῶς”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	σφιγκτός	tightly bound
2	Ancient Greek	-τός	creates verbal adjectives of possibility, either...
3	Proto-Indo-European	-tós	Creates verbal adjectives from verb stems

Every word from Proto-Indo-European -tós →Every word from Ancient Greek -τός →Every word from Ancient Greek σφιγκτός →