會彈回來的東西
這一組最貼近核心畫面：被撞、被踩、被壓之後，東西自己回到原位。差別只在誰動了——球自己飛回去，或人被推回來，或形狀長回來。
adjective · B1
A bouncy ball or other object springs back quickly every time it hits a surface, instead of landing and staying where it falls.
很會彈的
核心畫面
You can think of bouncy as a picture of something that will not stay pressed down. You drop it, you land on it, you push it flat — and it comes straight back at you. Nothing else is needed: no hand, no push, no help. The spring is inside the thing itself. Every use of the word keeps that one movement, and only changes what is doing the springing: a ball off the floor, a bed under a child, hair after a night on the pillow, a person through a whole day, a beat through a song.
「bouncy」可以想成一個「壓不住」的畫面。丟下去、踩上去、把它壓扁，它都會自己彈回來。不需要人再出手，那股力氣本…更多收起
「bouncy」可以想成一個「壓不住」的畫面。丟下去、踩上去、把它壓扁，它都會自己彈回來。不需要人再出手，那股力氣本來就在東西裡面。這個字的每一個用法都保留同一個動作，只是換了彈的主角：球從地板彈起來、床把人推回去、頭髮睡過一晚還站得起來、人一整天都有精神、拍子在歌裡一直往上跳。From the word’s history
Wiktionary records bouncy as bounce + -y, the adjective ending that turns an action into a description. So the word literally means 'having bounce in it', which is exactly the picture the modern senses share.
Wiktionary 記錄 bouncy 由 bounce（彈跳）加上形容詞字尾 -y 組成，字面就是「帶有彈跳性質的」。這條線索正好對上今天所有用法共用的那個畫面：力氣在東西自己身上。
Wiktionary entry 'bouncy' (kaikki snapshot 3f6f69a190036ae4): 'From bounce + -y.'
Two branches
像在彈跳的活力
把彈跳從物體搬到看不見的東西上。彈性好的球不用人幫忙就一直動；有活力的人和輕快的節奏給人的感覺一樣，能量自己會往上冒。
adjective · B1
Someone who is bouncy is happy, confident and full of energy, so they move, talk and react as if something inside them keeps springing up.
活力十足的