cinder

Cinder generally refers to the solid residue remaining after burning, typically small, partly burnt bits of wood or coal. They are heavier than ash, often black or gray, and may stay warm. In everyday use, cinders describe the scorched fragments left after a fire; the term is often used in the plural as 'cinders'.

In volcanology, cinders are a form of tephra: roughly 2 to 64 millimeters in diameter, rounded to oval-shaped volcanic fragments ejected during eruptions. Accumulations of cinders can form cinder cones; they are coarser than ash but finer than lava bombs.

In computing, Cinder is a cross-platform C++ library for creative coding, aimed at artists and developers for building visuals, audio, and interactive media. It provides a framework of APIs for graphics, audio, events, and networking, and runs on Windows, macOS, iOS, and Android.

In fiction, Cinder is the title character of The Lunar Chronicles by Marissa Meyer (2012). Cinder is a teenage cyborg mechanic living in New Beijing; the novel blends fairy tale elements with science fiction and follows her role in a broader interplanetary conflict.