spindel

Spindel is a term used in German and Dutch for spindle and is also encountered in English as spindle. It denotes several distinct concepts in different fields. This article outlines the main senses: machinery, textiles, and cell biology.

Spindel in machinery refers to the rotating axis of a machine tool that carries a cutting tool or holds the workpiece. The spindle transmits power and torque from the drive to the tool, and its rigidity affects precision. It is usually supported by bearings and driven by belts or direct drive. Spindles may be vertical or horizontal and accept different tool-holding standards and tapers, depending on the machine type.

Spindel in textiles is a hand tool used to spin fibers into yarn. A spindle consists of a shaft and a weighted whorl that provides momentum. With practice, fibers are twisted as the spindle turns and the thread is wound on the shaft. Common forms include the drop spindle and the supported spindle. Spindles have been used since ancient times and remain in artisanal crafts.

Spindel in biology refers to the spindle apparatus that organizes and separates chromosomes during cell division. Microtubules emanate from spindle poles and attach to kinetochores on chromosomes. During metaphase, chromosomes align at the cell equator; in anaphase, sister chromatids are pulled apart and moved toward opposite poles. The spindle is assembled anew each division and is regulated by motor proteins and microtubule dynamics.

Other uses: The term spindle appears in botany as spindle-shaped (tapering at both ends) and in common names such as the spindle tree (Euonymus europaeus).