- the world's first seismograph invented by Zhang Heng 张衡【Zhāng Héng】 in 132
- abbr. for 候风地动仪【hòu fēng dì dòng yí】
Generated: This meaning refers to an ancient device used to detect and measure earthquakes, signifying an important advancement in the field of seismology.
Zhang Heng invented the world's first seismograph in the year 132.
Generated: This refers to the abbreviated form of a specific type of seismograph that was designed to indicate the direction of wind along with seismic activity.
The anemoseismograph can measure both wind direction and earthquakes simultaneously.