A "smoking remnant" usually refers to a leftover ash or cigarette butt, but there are many other ways to describe this unpleasant waste. You could call it a discarded cigarette, spent tobacco, or burnt residue. Alternatively, it might be referred to as a smoldering remainder, an extinguished stub, or a flickering cinder. Other synonyms include a butt end, a smoking butt, or an ash-covered end. Ultimately, the choice of language depends on the situation, the intended tone, and the level of formality. Whatever the case, it is important to remember that smoking remnants should always be disposed of properly to avoid littering and potential fire hazards.