- 1死忠的、徹頭徹尾的（信念或喜好改不了；台灣常說「死忠」，對岸較常說「鐵桿」）
A -in-the-wool person has beliefs, likes, or opinions so deep that they will not change. We usually put it before a noun: a -in-the-wool football fan, a -in-the-wool conservative. It is a colourful, slightly old-fashioned phrase — more in writing and vivid speech than in everyday teen talk. The picture behind it is cloth. Fabric can be after it is woven, or the threads can be first. When a colour is in the wool, the wool itself is before it is spun into thread, so the colour is least likely to fade. So the idea is: this person is that colour all the way through. Though actually, nobody is thinking about sheep when they say it; they just mean “this will never change.”
From the word’s history
From dye in the wool: wool dyed before it is spun into thread, so the colour holds fast.
源自羊毛紡成線前就先染色，這樣顏色最不容易褪。
組成From the past participle of dye in the wool. The woven fabric may be dyed after it is complete, or the threads may be dyed before they are woven. When a colour is dyed in the wool, the wool itself is dyed before being spun into threads, so the colour is least likely to fade or change.
原始詞典資料2 筆記錄
以下是外部詞典記錄的用法，摘錄並精簡格式，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。
dyed-in-the-wooladj/ˌdaɪd ɪn ðə ˈwʊl/
- 1
Having the fibres dyed before they are formed into cloth.
- […] some Druggets with Thread, that are dyed in the Piece; the others are dyed in the Wool, i. e. the Wool of which they are made, is dyed of several Colours, before it is carded, spun, and weaved.
- That cloth will keep its colour best that is dyed in the wool; and the vessel will longest retain the scent of that liquor with which it is first seasoned.
- 2
Firmly established in one's beliefs or habits; having a specified characteristic, identity, etc. deeply ingrained in one's nature.
- Smith was a dyed-in-the-wool typist and never really got used to writing on computers.
- John Major was described by his opponents as a dyed-in-the-wool Conservative.
摘錄自 英文維基詞典 English Wiktionary，已精簡格式；依 CC BY-SA 4.0 授權使用，改動後的內容同樣以此授權提供。