Negligibly

Negligibly is an adverb that describes something as so small or unimportant that it can be treated as insignificant for practical purposes. It qualifies a quantity, effect, or difference and is common in technical and analytical writing.

Etymology traces negligibly to the adjective negligible, from Latin negligibilis “able to be neglected,” itself from neglegere “to neglect.” The suffix -ly forms the English adverb.

Usage in science, engineering, and statistics often signals that a quantity falls below a defined threshold or tolerance. It conveys practical insignificance rather than a precise mathematical zero; the specific threshold is determined by the context, standards, or conventions of a given field. The word is typically paired with terms like error, impact, or difference to emphasize that residual effects are not meaningful within the analysis.

Examples are common in technical reporting: “The rounding error is negligibly small,” “The overhead cost is negligibly affected by the optimization,” or “The two methods yield negligibly different results within experimental error.” Caution is advised, because what is negligibly small in one setting may be non-negligible in another, depending on criteria, precision, and stakes.

See also: negligible, insignificance, practical significance, threshold.