mantra of the fire realm; mantra of Acala
In esoteric Buddhism (密教), a mantra associated with Acala (不動明王) used to burn away worldly desires and spiritual obstacles. Highly domain-specific; not used in everyday language.
In esoteric Buddhist rituals, the mantra of the fire realm is chanted to burn away worldly desires.
From 火界 (fire realm) + 咒 (mantra/spell). The exact historical derivation is uncertain, but the term is a technical compound used in esoteric Buddhist texts.