From Wiktionary, the free dictionary
тене́й • (tenéj) f inan pl
- genitive plural of тень (tenʹ, “shade, shadow”)
те́ней or тене́й • (ténej or tenéj) f anim pl or f inan pl
- inflection of тень (tenʹ, “apparition, ghost”):
- genitive plural
- animate accusative plural