mechanical; automatic; unthinking
Describes actions, processes, or behavior that are done without thought, like a machine. Can be neutral or slightly negative when applied to people.
His reply was mechanical and lacked sincerity.
In the factory, robots perform mechanical tasks.
自動的 focuses on a process occurring without human decision, while 機械的 emphasizes doing something in a mechanical, unthinking way, sometimes describing human behavior too.
機械的 stresses an automatic, thoughtless machine-like quality, while 事務的 stresses a bureaucratic, office-like lack of warmth.
Compound of 機械 (machine) + 的 (-like, adjectival suffix).