* Palindrome: This is the most common term, but technically it refers to words, phrases, or sequences that read the same forwards and backward. While many palindromes do change when spelled backward, some simply remain the same.
* Reverse anagrams: This term is more specific, as it explicitly indicates that the backwards spelling results in a different word.
* Antigram: This is a less common term, but it accurately describes words that are the reverse of another word.
* Backwards word: This is a simple and straightforward description.
Ultimately, the best term depends on the context and your desired level of specificity.