Picture running a pen right along the edge of something. Before you do, it blurs into the background; after you do, anyone can see where it stops and where everything else begins. Each use of define is drawing that edge — sometimes around a shape you can see, sometimes around a meaning or a job.
From the word’s history
From Latin definire 'to limit, determine, explain', from de- 'completely' + finire 'to bound, limit', from finis 'that which divides, a boundary, border, end'. It came into English in the late 14th century meaning 'to fix or establish authoritatively'. So defining something is, at root, drawing the line around it.
來自拉丁文 definire「限定、確定、說明」，由 de-（完全地）加 finire（設下界線）組成，而 finire 的源頭是 finis——「劃分開來的東西、邊界、盡頭」。英文在 14 世紀晚期借入，一開始就帶著「把範圍定下來」的意思。所以「下定義」在字源裡其實就是「畫出邊界」這件事。
Online Etymology Dictionary (etymonline.com), entry 'define (v.)'
登入就可以看每一支怎麼連回核心畫面。
原始詞典資料8 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。
defineverb/dɪˈfaɪn/
- 1
To determine with precision; to mark out with distinctness; to ascertain or exhibit clearly.
- the defining power of an optical instrument
- Rings[…]very distinct and well defined.
- 2
obsoleteTo settle, decide (an argument etc.).
- These warlike Champions, all in armour shine, / Assembled were in field the chalenge to define.
- 3
To express the essential nature of something.
- I define myself as a techno-anarchist.
- Your past mistakes do not define who you are.
- 4
To state the meaning of a word, phrase, sign, or symbol.
- The textbook defined speed as velocity divided by time.
- 5
To describe, explain, or make definite and clear; used to request the listener or other person to elaborate or explain more clearly his or her intended meaning of a word or expression.
- Person 1: Is she good at math? Person 2: Define "good." If you mean if she is faster than the average middle schooler at multiplication, then yes. If you mean if she is able to do multivariable calculus, then no.
- 6
To demark sharply the outlines or limits of an area or concept.
- to define the legal boundaries of a property
- Neither Marx nor Engels ever clearly defined the concept of class, and the last chapter of Volume III of Capital, which was to treat of this question, breaks off after three or four paragraphs.
- 7
mathematicssciencesTo establish the referent of a term or notation.
definenoun/dɪˈfaɪn/
- 1
computingengineeringmathematicsA kind of macro in source code that replaces one text string with another wherever it occurs.
- From the computer programming perspective, Java looks like C and C++ while discarding the overwhelming complexities of those languages, such as typedefs, defines, preprocessor, unions, pointers, and multiple inheritance.
- Anyone who has attempted to do OO programming in a conventional language using defines will find out that it is impossible to realize the benefits easily, if at all, without compiler support.
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。