nonnoxious

Nonnoxious is an adjective used to describe something that is not harmful, not poisonous, or not injurious to health or the environment. It signals the absence of properties implied by the word noxious, which typically refers to substances, odors, or conditions that are clearly harmful or offensive.

Etymology and form: the term is built from the prefix non- joined to the adjective noxious. Noxious itself comes from Latin noxius meaning injurious. In contemporary writing, nonnoxious is relatively uncommon; many writers instead use non-noxious (hyphenated) or prefer established terms such as harmless, benign, innocuous, or safe.

Usage and nuance: nonnoxious appears most often in technical, regulatory, or risk-assessment contexts where precise characterization of safety is important. It can be used to describe chemicals, products, or environmental exposures that do not pose known risks under specified conditions. Because the word is rarely used in everyday speech, readers may encounter it as a formal or somewhat unusual choice.

Limitations: because noxious is a strong term, some readers may question the need for a formal opposite. In practice, writers frequently substitute clearer, more common terms like harmless or nonhazardous to avoid ambiguity. See also: innocuous, harmless, nonhazardous, safe.