粉こな石せっけん

こ

な

せ

っ

け

ん

Meanings

1

noun

soap powder; powdered soap

Refers to soap in powdered form, used for laundry or cleaning.

粉こな石せっ鹸けん

Alternate kanji spelling using 鹸.

石せっけん
石けん is general soap (often bar soap), while 粉石けん specifically means powdered soap.
洗せん剤ざい
洗剤 is a broader term for detergent, including synthetic detergents, whereas 粉石けん is natural soap powder.

Compound of 粉 (こな, 'powder') and 石けん (せっけん, 'soap').