開心到動起來的玩鬧
動詞和名詞是同一個畫面的兩種包裝：一個在演，一個在指。
verb · B2
To play and move about in a lively, happy way — running, jumping, rolling or chasing, because you feel good.
嬉戲、歡鬧
核心畫面
One way to hold this word: a young animal or a child who feels so good that the feeling will not stay inside — so it comes out as running, jumping, splashing and chasing, with nowhere in particular to get to. The movement has no purpose except the mood that started it. The verb is that moment happening; the noun is that moment packed up and given a name.
frolic 的畫面可以想成：一隻小動物、或一個小孩，開心到那股勁待不住，於是整個人跑起來、跳起來、踩水、追來追去。…更多收起
frolic 的畫面可以想成：一隻小動物、或一個小孩，開心到那股勁待不住，於是整個人跑起來、跳起來、踩水、追來追去。這些動作沒有要去哪裡，也沒有要完成什麼。它們就只是那個心情跑出來的樣子。動詞講的是這一刻正在發生；名詞則是把這一刻包起來、給它一個名字。From the word’s history
The source traces frolic to Dutch vrolijk, meaning cheerful, and links it to German fröhlich. So the word begins as a name for a mood, and the modern uses are that mood turned into movement.
字源資料說 frolic 來自荷蘭文 vrolijk（愉快的），跟德文 fröhlich 同源。也就是說，這個字一開始講的是心情，不是動作。今天的用法可以想成心情長出了身體：開心到坐不住，於是變成跑跳。這也解釋了為什麼 frolic 一定要動起來，而 play 可以安安靜靜。
Wiktionary (kaikki extract, source_ref kaikki:3f6f69a190036ae4:782313577:17824): "From Dutch vrolijk (cheerful) ... Compare German fröhlich"
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