noun
in very small pieces; smashed to bits; pulverized
Describes something broken or crushed into tiny fragments, often used with verbs like 砕ける or する. The reading こみじん is a colloquial contraction.
花瓶が落ちて粉微塵に砕けた。
The vase fell and shattered into tiny pieces.
彼の自信は粉微塵になった。
His confidence was completely shattered.
粉々 also means 'in small pieces' but is more common and neutral. 粉微塵 emphasizes even finer destruction or complete ruin.
Compound of 粉 (こな, 'powder') and 微塵 (みじん, 'tiny particles'). The reading こみじん is a contraction of こなみじん.