noun, noun or participle which takes 'suru', intransitive verb
Astronomical term for a body spinning around its own axis, contrasted with 公転 (revolution around another body).
See also: 公転
地球の自転は約24時間で一周する。
The Earth's rotation takes about 24 hours to complete one turn.
noun, noun or participle which takes 'suru', intransitive verb
rotation (under its own power)
General use for something turning by itself, such as a wheel or a motor-driven part.
モーターが自転してファンを回す。
The motor rotates under its own power and turns the fan.