抹到看不出來
這一支就是核心畫面本身，加上把同一個動作放大到整個實體東西上的用法。
verb · C1
To rub out, cross out or smear writing, a drawing or a mark, so that nobody can read or make out what was there.
塗掉／抹到看不出字
核心畫面
One way to hold this word: a page with writing on it, and a hand passing over the writing until you cannot read a single letter. The paper is still there. The marks may even still be there. What has gone is the thing you could read. Every other use of obliterate does that same move to something bigger — a building, a view, a memory — and the test is always the same: go and look, and there is nothing left to make out.
這個字可以想成一張寫著字的紙，有一隻手在上面抹過去，抹到一個字母都認不出來。紙還在。痕跡也許還在。不見的是「可以讀出…更多收起
這個字可以想成一張寫著字的紙，有一隻手在上面抹過去，抹到一個字母都認不出來。紙還在。痕跡也許還在。不見的是「可以讀出來的東西」。這個字其他的用法，都像是把同一個動作放大：對象換成一棟房子、一片風景、一段記憶。而檢查方法永遠一樣——回去看一眼，什麼都認不出來了。From the word’s history
Wiktionary derives obliterate from Latin obliterātus / oblitterātus, the participle of obliterō, probably from ob- ('against, towards') plus littera ('letter') — literally to blot out written letters. The writing sense is therefore the one closest to the word's own parts.
字典說 obliterate 借自拉丁文 obliterātus／oblitterātus，是 obliterō 的分詞；這個動詞很可能由 ob-（對著、朝向）加 littera（字母）組成，字面上就是「把寫下的字塗掉」。所以「抹掉字跡」這個用法，最貼近這個字本身的組成。
Wiktionary via kaikki extract, source_ref kaikki:3f6f69a190036ae4:512180880 (etymology 1 of obliterate)
Three branches
蓋到看不見
同樣是「讓人看不出來」，但這次東西完全沒事，被抹掉的只是你眼睛看到的那一層。
verb · C1
To cover something so completely that it cannot be seen at all.
遮蔽到看不見
從心裡抹掉
把同一個動作移到心裡：記憶像寫在腦子裡的字，被抹掉就再也叫不出來。
verb · C1
To take a thought, a feeling or a memory completely out of someone's mind, so that it no longer stays there at all.
從腦中抹去