What is the name for a word that spelled backwards forms another word?

There isn't a single, universally accepted term for a word that spells another word backwards. However, there are a few terms that are commonly used:

* Semordnilap: This is a playful combination of "palindrome" and "anagram" and is the most common term. It's also known as a reverse anagram.

* Word pair: This is a more general term that can also refer to words that are related in other ways, like synonyms or antonyms.

* Reverse spelling: This is a simple and straightforward description.

Some examples of these words include:

* stressed/desserts

* drawer/reward

* stop/pots

So, while there isn't a single, official name, you can choose the term you find most appropriate for the context.