把東西壓平
這一族是核心畫面最直接的用法：對象是物體，動作是讓它失去高度。
make flat · verb · C2
To press or change something so it is even and not raised, or to become even and low like that.
壓平
核心畫面
One way to picture it: something that stood up with height or bumps gets pressed down until it is level with the surface under it — the shape loses its rise.
本來有高度、有起伏的東西，被一股力量往下壓，直到跟底下的平面貼在一起、不再突起。flat 是「平」，加上 -en 就…更多收起
本來有高度、有起伏的東西，被一股力量往下壓，直到跟底下的平面貼在一起、不再突起。flat 是「平」，加上 -en 就成了「使它變平／變得平」。重點不在破壞，而在「高度消失」這個動作本身——麵團被擀開、皺紙被撫平、輪胎沒氣扁掉，都是同一個畫面。From the word’s history
flatten = the adjective flat + the verb-forming suffix -en, so it literally means 'to make flat'; flat itself comes through Middle English from Old Norse flatr, from Proto-Germanic *flataz.
flatten 的組成很直白：形容詞 flat（平的）加上動詞後綴 -en（使…變成…），字面就是「使變平」。flat 經中古英語上溯到古諾斯語 flatr、再到原始日耳曼語 *flataz。所以這個字從造字的那一刻起，講的就是「把高度壓掉」這件事，後面所有意思都是這個動作用在不同東西上。
Etymology tree supplied with this entry (Proto-Germanic *flataz → Old Norse flatr → Middle English flat → flat + -en → flatten)
Two branches
把人或隊伍打倒
這一族把「壓到不再立起來」搬到人身上：對手原本站著（或聲勢正旺），一擊之後倒下、抬不起頭。中文的「壓倒性」剛好共用同一個比喻。
knock someone down · verb · C2
To hit someone very hard, so they fall or cannot stay on their feet.
撞倒
原始詞典資料9 筆記錄
以下是外部詞典記錄的用法，原文照列，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
flattenverb/ˈflæ.tən/
- 1
To make something flat or flatter.
- As there was a lot of damage, we chose the heavy roller to flatten the pitch.
- Mary would flatten the dough before rolling it into pretzels.
- 2
To press one's body tightly against a surface, such as a wall or floor, especially in order to avoid being seen or harmed.
- With a bolt of fright he remembered that there was no bathroom in the Hob-house Room. He leapt along the corridor in a panic, stopping by the long-case clock at the end where he flattened himself against the wall.
- 3
To knock down or lay low.
- The prize fighter quickly flattened his challenger.
- 4
To become flat or flatter; to plateau.
- Prices have flattened out.
- 5
To be knocked down or laid low.
- 6
entertainmentlifestylemusicTo lower by a semitone.
- 7
To make vapid or insipid; to render stale.
- 8
computingengineeringmathematicsTo reduce (a data structure) to one that has fewer dimensions, e.g. a 2×2 array into a list of four elements.
另外 1 個記錄的用法
- 9
computer-graphicscomputingengineeringTo combine (separate layers) into a single image.
資料來源：英文維基詞典 English Wiktionary（CC BY-SA 4.0）。 原文照列，未經改寫。