The word "untoothed" is a term that is often used to describe an object or a surface that is smooth or lacks teeth. However, there are several synonyms that can be used instead of "untoothed" to add more variety and depth to your writing. Some of these synonyms include "smooth," "plain," "untextured," "unridged," "flawless," "featureless," "undent," "unnotched," "undulate," "unscalloped," and "uncreased." These words can help make your writing more interesting and descriptive by avoiding repetitive language and creating a more vivid image in the reader's mind. Overall, there are many synonyms for "untoothed," and using them can take your writing to the next level.