在腦子裡慢慢磨
小火慢煮的那口鍋放進腦袋裡：問題不急著答，放著讓它自己變清楚。
verb · B2
To think about a problem, plan, or idea slowly and carefully for a long time before you decide. It is almost always used as mull over.
反覆琢磨
這個拼法底下其實是2個不同的字，意思沒有關係， 只是長得一樣。下面分開列出來。跳到 反覆琢磨 · 海岬（蘇格蘭用法）
1
mull
v核心畫面
One way to hold the verb: something is left in the pot on a low heat. Nothing is rushed, nothing is forced, and the change happens because time is allowed to do the work. In the head, that is a question you keep turning over until the answer settles. In the kitchen, it is a drink kept warm with until the flavour comes out. Both are slow, both are patient, and in both the point is what you get at the end of the waiting.
可以想成鍋子開著小火，東西就放在裡面。不趕，不硬逼。改變是靠時間慢慢發生的。放在腦子裡，那就是一個問題被你一直翻來覆…更多收起
可以想成鍋子開著小火，東西就放在裡面。不趕，不硬逼。改變是靠時間慢慢發生的。放在腦子裡，那就是一個問題被你一直翻來覆去，直到答案自己沉澱下來。放在廚房裡，那就是一鍋加了香料的飲料被暖著，直到味道出來。兩邊都慢，兩邊都要等。而且兩邊看重的都是「等完之後得到的那個東西」。From the word’s history
The source traces the verb to Middle English molle/mulle ('dust, rubbish'), possibly from Old English myl, and says it is related to English mill, 'to grind'. It adds that some verbal senses come instead from Middle English mollen, 'to soften, dissolve'. Grinding fine and softening slowly are both there in the record, which fits a word about letting time work on something.
來源把這個動詞接到中古英語 molle／mulle（灰塵、碎屑），可能再往前是古英語 myl，並說它和 mill（磨）有關。來源又補了一句：有些動詞用法其實來自中古英語 mollen（使變軟、溶解）。「磨細」和「泡軟」這兩條線索都在資料裡，正好對上一個講「讓時間慢慢起作用」的字。
Wiktionary (kaikki snapshot 3f6f69a190036ae4), mull verb etymology 1: 'Inherited from Middle English molle, mulle (dust, rubbish) … related to English mill (to grind). … Some verbal senses are supplied by Middle English mollen (to soften, dissolve), from Old French moillier.'
Two branches
在鍋裡慢慢煨出味道
同樣是小火加時間，只是這次真的在鍋子裡：等的是香料的味道出來。
verb · C1
To heat a drink — wine, cider, or fruit juice — together with sugar and spices such as cinnamon, cloves and orange peel. You usually meet it as the form mulled in front of the drink.
加糖和香料煮熱（飲料）
A second word, same spelling
2
mull
n核心畫面
A completely separate word that happens to be spelled the same. Here, think of standing on a coast road in Scotland and watching the land run out: a high, rounded head of ground pushing into the sea, with water on three sides and usually a lighthouse at the tip.
這是另一個字，只是剛好拼成一樣。可以想成你站在蘇格蘭的濱海公路上，看著陸地一路跑到盡頭：一塊高高圓圓的地伸進海裡，三…更多收起
這是另一個字，只是剛好拼成一樣。可以想成你站在蘇格蘭的濱海公路上，看著陸地一路跑到盡頭：一塊高高圓圓的地伸進海裡，三面是水，尖端上常常還立著一座燈塔。From the word’s history
The source gives this noun a separate origin: Scottish Gaelic maol. It is not a figurative use of the verb; it is a different word that English borrowed from Gaelic, which is why it stays tied to Scottish places.
來源給這個名詞另一條來歷：蘇格蘭蓋爾語 maol。它不是動詞義引申出來的比喻，而是英文從蓋爾語借進來的另一個字。這也說明為什麼它一直黏著蘇格蘭的地名。
Wiktionary (kaikki snapshot 3f6f69a190036ae4), mull noun etymology 3: 'From Scottish Gaelic maol.'