Which term indicates something that is not legally significant?

The term that indicates something that is not legally significant is "de minimis." This Latin phrase translates to "about minimal things" and is often used in legal contexts to refer to matters or issues that are too small or trivial to merit consideration. In legal disputes, de minimis issues do not typically warrant a legal remedy or attention because their impact is negligible.

By contrast, the other terms carry more substantial legal implications. "De novo" refers to considering a matter anew, often in terms of a new trial or review, while "dictum" relates to remarks made by a judge that are not essential to the decision and may carry persuasive weight but are not binding. "Cum laude" refers to an academic honor indicating a degree earned with distinction, which is also not related to legal significance. Thus, "de minimis" is the correct choice as it directly identifies something as insignificant in the legal context.