h₂eys-
“to be in awe, to revere, to be fiery”Awe, revere, fire
A PIE root meaning "to be in awe, to be passionate or fiery," reflected in Greek hierós (ἱερός, "sacred, holy"), whence hierarchy, hieroglyphic, and hierophant; and in Latin īra ("anger"), whence ire and irate. The semantic range spans sacred awe to anger — both states of intense emotional arousal.
Discussion
The root *h₂eys- ("to be in awe, to move with passion") is reconstructed from Greek hierós (ἱερός, "sacred, holy, powerful"), Latin īra ("anger, wrath"), Sanskrit iṣ- ("to be vigorous, to refresh"), and Avestan aēša- ("seeking"). Pokorny (IEW 12, 299) and Beekes (s.v. ἱερός) discuss the root, though the exact semantic reconstruction is debated.
Greek hierós (ἱερός, "sacred, holy") is the most culturally prominent reflex, generating an extensive vocabulary: hierarchy (hierarkhía, "rule of the sacred"), hieroglyphic (hieroglyphikós, "sacred carving"), hierophant ("one who reveals sacred things"), and the proper name Hieronymus (Jerome). The semantic core in Greek is the numinous, the powerfully sacred.
Latin īra ("anger, wrath") preserves a different semantic facet — intense emotional arousal. English ire, irate, and irascible derive from this branch. The connection between sacred awe and anger (both states of intense emotional agitation) is semantically plausible and paralleled in other IE roots.
The word iron is sometimes connected to this root through Celtic: Old Irish íarn, from Proto-Celtic *īsarno-, possibly meaning "the strong/holy metal." This etymology remains disputed; an alternative derivation from a non-IE substrate word has been proposed.
Sanskrit iṣ- ("to be vigorous, to be refreshed") and iṣirá- ("vigorous, refreshing") preserve the Indo-Iranian branch. The overall semantic trajectory — from vital force through sacred power to anger — represents a coherent if complex development.
Notes
gsc-gap: source of "hierarchy", "hieroglyphic", "ire", "irate"
Laryngeal Analysis
Initial *h₂- colours following vowel; lost in most branches.
Ablaut
Full grade *h₂eys-, zero grade *h₂is-.