on Just Publishing Advice:
Amazon keywords are often called hidden keywords.
When you sell on Amazon, you can optimize your product by adding keywords to your Amazon listing.
These words do not appear on your Amazon product page, but they will hopefully appear when customers use search queries to find what they are looking to purchase.
Searches on Amazon work in a similar way to search terms on Google or Bing. You need to find relevant keywords to attract the attention of a buyer.