This adjective describes something related to a mill, particularly a millstone used for grinding grain. In Luke 17:2, Jesus warns that it would be better to have a millstone hung around one's neck and be thrown into the sea than to cause a little one to stumble. The multilingual glosses identify millstone (Spanish de molino, French meule). The image evokes the large stones rotated to crush grain—heavy enough to ensure drowning. Jesus uses this shocking imagery to emphasize the severity of causing spiritual harm to vulnerable believers.