加速度
かそくど · kasokudo · JLPT N2 · noun
acceleration
🚀 加速度 = 加 add + 速 speed + 度 degree: how fast your speed increases
速 is speed and 加 means add, so 加速 is speeding up and 度 measures how much. The same 加速 word labels a car's accelerator pedal.
加 — force 力 + mouth 口
加 is traditionally analyzed as a compound of 力 (strength) and 口 (mouth), suggesting boasting or exaggerating one's effort with words. From this it extended to the meaning 'to add' or 'increase'. Today it is used broadly for addition, both literal and figurative.
度 — 广 (shelter) + 庶 abbreviated (phonetic)
Originally depicted a hand measuring length under a shelter, meaning 'to measure' or 'a measure/standard.' From this came extended senses like 'degree,' 'extent,' and 'to pass through' (as in passing time). The reading 'dù' means degree/measure, while 'duó' preserves the older verbal sense of measuring.