Where does “ventriloquium” come from?

ventriloquium (Latin) comes from Latin loqui, from Latin loquor, from Proto-Italic tlokʷōr, from Proto-Indo-European telkʷ- — to talk.

Ancestry of “ventriloquium”, step by step

Step	Language	Word	Meaning
1	Latin	loqui	present active infinitive of loquor; to talk;...
2	Latin	loquor	I say, speak, tell, talk; I declare, utter
3	Proto-Italic	tlokʷōr	—
4	Proto-Indo-European	telkʷ-	to talk

ventriloquium — Etymology, Origin & Word History | Etymology Explorer