This is the 709th most frequent Greek word.
διεθνούς
"Of international" or "international."
Here, 'διεθνούς' acts as an adjective meaning 'international' to describe 'επιπέδου' (level).
Η συνεργασία διεθνούς επιπέδου απαιτεί ευελιξία.
International level cooperation requires flexibility.
In this sentence, 'διεθνούς' serves as an adjective describing 'φήμης' (fame or reputation), implying well-known internationally.
Η έκθεση φιλοξενεί έργα τέχνης διεθνούς φήμης.
The exhibition hosts artworks of international acclaim.
The word 'διεθνούς' is used as an adjective to denote 'interest' as being of a global nature.