What is HG? HG stands for Holy Grail. This is used to refer to products which you have tried and proven to offer you the best results and which become a staple in your regimen. POSTS RELATED TO THIS TERM How To Detangle 4c Natural Hair: Holy Grail Product for Reducing … Why Scalp Exfoliation Is My Personal Holy Grail Cleansing Method … Oil Rinsing; The Holy Grail Of Black Hair Care? TweetPinShare0 Shares Home » Glossary » H » What is HG?