What does Tēnos mean in Latin?

Tēnos, a proper noun, means “Tinos”.

What is the genitive of Tēnos?

The genitive singular is Tēnī. Tēnos is feminine, second declension.

In classical Latin, [ˈteː.nɔs]; in ecclesiastical (church) Latin, [ˈtɛː.nos].

proper noun · femininesecond declension

Tēnos f sg (genitive Tēnī)

Classical[ˈteː.nɔs]Ecclesiastical[ˈtɛː.nos]

Tēnos or -us, i, f., = Τῆνος,

I. one of the Cyclades, between Andros and Delos, now Tino, Mel. 2, 7, 11; Plin. 4, 12, 22, § 65; Liv. 36, 21; Ov. M. 7, 469.

Borrowed from Ancient Greek Τῆνος (Tênos).