“Lest” is used in formal contexts to convey subtle warnings by indicating a potential negative consequence or outcome that needs to be avoided. As a conjunction, its primary function is to introduce a clause that expresses a possible result that should be prevented.

In professional and academic writing, “lest” is often employed to add a tone of caution or concern. It is utilized to point out the potential risks or consequences of certain actions, thereby serving as a means to advise against taking those actions. By using “lest,” writers can convey a sense of prudence, alertness, and foresight, which are crucial in formal communication settings where precision and clarity are essential.

Overall, the inclusion of “lest” in writing helps to highlight specific dangers, pitfalls, or undesirable outcomes that the audience should be aware of or take measures to avoid, thereby enhancing the effectiveness of the warning or advice being given.