A word or phrase that, when spelled backwards, produces a different word or phrase. While a palindrome spells the same word both forwards and backwards, an emordnilap spells a different word each way.
Palindrome and emordnilap are emordnilaps, and therefore ‘emordnilap palindrome’ is a palindrome.
Synonyms: "Semordnilaps are also known as heteropalindromes, semi-palindromes, half-palindromes, reversgrams, reversible anagrams, word reversals, or anadromes. They have also sometimes been called antigrams, though this term now usually refers to anagrams with opposing meanings." Source : Wikidictionary
Also sometimes known as an emordnilap. Some may consider semordnilap to be the plural form.
Q. If the queen buys a pint, does that make it a regal lager?
A. Dude, that's a semordnilap