strongsmelling

Strong-smelling is a term used to describe odors perceived as intense by the human olfactory system. The perceived odor strength depends on the concentration of odorant molecules, their volatility, the sensitivity of the observer, and environmental factors such as temperature and humidity. The phrase is subjective and often context-dependent; what is strong to one person may be moderate to another.

Odors with strong smell can originate from foods (garlic, onions), spices, perfumes, solvents, petrochemical emissions, and decaying matter. In industrial and environmental settings, odor strength is an important nuisance parameter; regulation may require monitoring and mitigation of strong odors to protect public comfort and property values. Strong odors may be pleasant, such as perfume or baked bread, or unpleasant, such as rotten eggs or solvents.

Scientists measure odor intensity using sensory panels and scales, or instrumental proxies like volatile organic compound concentration. Dynamic olfactometry and odor units (ou/m3) quantify odor concentration relative to a standard reference. Individual differences in smell sensitivity, age-related decline, and conditions like anosmia or hyperosmia influence perceived strength.

In standard English, the usual form is strong-smelling as a compound adjective; "strong smell" as a noun phrase, and the hyphenation helps readability. The unhyphenated "strongsmelling" appears mainly in informal or typographical contexts and is generally avoided in formal writing.