Effluvium is defined as a disagreeable or noxious vapor or smell. In contrast to "more effluvia," the antonyms would be clean, odorless, and fresh. Other antonyms for effluvium include fragrant, sweet-scented, and pleasant. To avoid effluvia, one can use air-fresheners, open windows, or invest in air purifiers. Regular cleaning and proper ventilation can also reduce the presence of effluvium in enclosed spaces such as homes, offices, and public places. In summary, the opposite of "more effluvia" would involve a pleasant and fresh atmosphere that is devoid of disagreeable and harmful odors.