Where does “Terpsícore” come from?

Terpsícore (Portuguese) comes from Latin Terpsichorē, from Ancient Greek Τερψιχόρη, from Ancient Greek τέρψις, from Ancient Greek -σῐς, from Ancient Greek -τις, from Proto-Indo-European -tis — Derives abstract/action nouns from verb roots.

Terpsícore (Portuguese): Terpsichore one of the nine muses

Definitions

Terpsichore one of the nine muses

Ancestry of “Terpsícore”, step by step

Step	Language	Word	Meaning
1	Latin	Terpsichorē	—
2	Ancient Greek	Τερψιχόρη	Terpsichore
3	Ancient Greek	τέρψις	full enjoyment, delight, gladness, pleasure
4	Ancient Greek	-σῐς	"suffix forming nouns"
5	Ancient Greek	-τις	retained after dentals
6	Proto-Indo-European	-tis	Derives abstract/action nouns from verb roots

Every word from Proto-Indo-European -tis →Every word from Ancient Greek -σῐς →Every word from Ancient Greek -τις →