The more formal Japanese term for generic name Merbromin is メ【me】ル【ru】ブ【bu】ロ【ro】ミ【mi】ン【n】, and the term for brand name Mercurochrome is マ【ma】ー【a】キュ【kyu】ロ【ro】ク【ku】ロ【ro】ム【mu】. This topical antiseptic also goes by the informal name [赤]【aka】チ【chi】ン【n】, or older [赤]【aka】チ【chi】ン【n】キ【ki】.
- The [赤]【aka】 part simply expresses the sense of red, as the medicine is indeed red in color:
- The チ【chi】ン【n】 part is from older チ【chi】ン【n】キ【ki】, which in turn is an abbreviation of チ【chi】ン【n】キ【ki】テュ【tyu】ー【u】ル【ru】, a borrowing from Dutch tinktuur, cognate with English tincture (i.e., a solution of a medicinal substance in a liquid, usually alcohol).
The Japanese Wikipedia article suggests that the term arose from a slang use of チ【chi】ン【n】キ【ki】 to refer more specifically to ヨ【yo】ー【o】ド【do】チ【chi】ン【n】キ【ki】, or a tincture of iodine. Since iodine tinctures are more yellowy-brown in color, the [赤]【aka】 was added as a prefix to differentiate.