An adjective describing someone physically trembling, typically in response to encountering the divine or overwhelming holy presence. The word compounds en- (in) with tromos (trembling), capturing an embodied fear response. All three New Testament instances occur in moments of divine encounter: Moses before the burning bush, the Philippian jailer after the earthquake and supernatural prison opening, and the Israelites at Sinai. The consistent translation across languages as 'trembling' or 'shaking' reflects both the physical manifestation and the emotional root—reverent terror before what is holy and dangerous.