βρένθειον

From LSJ

ἁρμονίη ἀφανὴς φανερῆς κρείττων → the hidden attunement is better than the obvi­ous one, invisible connection is stronger than visi­ble, harmony we can't see is stronger than harmony we can, unseen harmony is stronger than what we can see

Source

German (Pape)

[Seite 463] od. βρένθιον, τό, ein wohlriechendes Salböl, Sappho u. Phereer. bei Ath. XV, 690 e.