na-adjective, noun
absolute purity; utter purity
Describes something completely pure, untainted, or unadulterated. Often used in literary or formal contexts.
彼の心は至純で、少しの悪意もない。
His heart is absolutely pure, without a trace of malice.
この水は至純な味わいだ。
This water has a taste of absolute purity.
純粋 is the common word for 'pure' in everyday contexts. 至純 is more emphatic and literary, meaning 'absolute purity'.
Compound of 至 (utmost) and 純 (purity). The exact historical derivation is uncertain, but the meaning is transparent from the kanji.