βροντώδης
From LSJ
Φίλον δι' ὀργὴν ἐν κακοῖσι μὴ προδῷς → Amicum ob iram deserere cave in malis → Verrate einen Freund nicht in der Not aus Zorn
English (LSJ)
ες,
A like thunder, thundering, κτύποι Agath.5.8, cf. Lyd. Ost.42, al., Sch.Ar.Ra.826. II charged with thunder, Vett.Val. 14.17, Ptol. Tetr.94.