The combination of words of various parts of speech is called synthesis.

Taking one part of speech as another part of speech in the same form is called transformation.

Adding a prefix before the root or a suffix after the root to form a new word with similar or completely opposite meaning to the original word is called derivation.

The method of mixing one word with another to form a compound word is called spelling.

What keeps abbreviations, meanings and parts of speech unchanged is called truncation.

Using the first letter and the last letter of a word to form a new word is called an acronym.