> [[nagy-g]]. Comment on [[iliad]]8.002 in [[chs-homer-commentary]]. > [hcp](https://nrs.chs.harvard.edu/v2/urn:cts:CHS:Commentaries.AHCIP:Iliad.8.2.zv3nZzJ.6) > This compound noun _terpi-kéraunos_, interpreted here as ‘he whose bolt strikes’, is an epithet that applies exclusively to Zeus: a parallel epithet, also applied exclusively to Zeus, is the compound noun _argi-kéraunos_ at Ι.19.121, I.20.016, I.22.178, which can be interpreted to mean ‘he whose bolt shines’ (GMP 195). Both epithets fit Zeus in his role as a thunder-god. The second part of both compounds _terpi-kéraunos_ and _argi-kéraunos_ is clearly derived from _keraunós_ ‘thunder’, and the first part of _argi-kéraunos_ is clearly related to _arg-ós_ (earlier `*argr-ós`) ‘shining, speeding’, but the first part of _terpi-kéraunos_ seems at first unclear. Related forms in other Indo-European languages, however, help elucidate the meaning of _terpi_- as combined with _keraunós_. In the case of _keraunós_, we find in the Baltic and Slavic branches of Indo-European the parallel forms _perkūnas_ and _perunŭ_ respectively, both of which are nouns meaning ‘thunder’ and/or ‘god of thunder’. Although the Greek and the Baltic/Slavic roots here, *_kerh2(u̯)-_ and *_per(kw)-_ respectively, are different in form, they are parallel in meaning, ‘strike’, and the morphology of their suffixation is also parallel (GMP 194–195). As for the _terpi_- of _terpi-kéraunos_, we find a comparable form in the Italic branch of Indo-European: it is the Latin noun _quercus_, meaning ‘oak tree’. This form, it can be argued, refers to the defining sacred moment when a thunderbolt strikes an oak tree: here the root of the _u_-stem noun _quercus_, from *_perkwu_-, is *_perkw_-, meaning ‘strike’ (GMP 186). So, _terpi-kéraunos_ can be derived from `*kwerpi-kéraunos` via metathesis from `*perkwi-kéraunos`.