7 skinby cathleen17. April 202019. April 20207 skin refers to a skincare layering technique. It’s very popular in K-Beauty and is mostly practiced with toners or lightweight essences. You apply several thin layers of the same product. 7 skin means 7 layers of product. Related « Back to Glossary Index Leave a Reply Cancel reply This site uses Akismet to reduce spam. Learn how your comment data is processed.