- 1極微小的；數學上說「無窮小」
Something infinitesimal is extremely small — so small you can barely treat it as a real size. Maths and science use it for a quantity that sits closer to nothing than to any ordinary number; in calculus, an infinitesimal step is a change so tiny it helps you talk about a smooth slope. In everyday English, people borrow it more loosely: an infinitesimal chance, an infinitesimal difference, meaning “tiny, almost not there.” It is a formal, educated word. You would not use it about a sandwich. Though actually, often meet infinite first and guess this must also mean “huge.” It is the other direction: infinite is without end; infinitesimal is without any real size. It can also be a noun in maths: an infinitesimal is one of those small quantities. An older maths word for a related idea was fluxion; infinitesimal took its place.
組成From New Latin īnfīnītēsimus + -al. The Latin was built like a “-th” form of infinite (as in thousandth, millionth): the infinite-th, a piece smaller than any ordinary piece. It displaced the older coordinate term fluxion.
同家族的字
- infinitesame ‘not having an end’ stem; this word turns that idea toward ‘impossibly small’
- infinitythe ‘no end’ noun from the same stem
- infinitesimallythe adverb made from this adjective
原始詞典資料5 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。
infinitesimaladj/ˌɪnfɪnɪˈtɛsɪməl/
- 1
Incalculably, exceedingly, or immeasurably minute; vanishingly small.
- Do you ever get the feeling that you are but an infinitesimal speck, swallowed by the vastness of the universe and beyond?
- "You will conceive a bunch of grapes," said he, "which are covered by some infinitesimal but noxious bacillus."
- 2
mathematicssciencesOf or pertaining to non-zero quantities whose magnitude is less than any positive rational number.
- 3
informalVery small.
infinitesimalnoun/ˌɪnfɪnɪˈtɛsɪməl/
- 1
mathematicssciencesA non-zero quantity whose magnitude is smaller than any positive number (by definition it is not a real number).
- 2
Something infinitesimally small.
- It occurred to the hearer, who was accustomed to glean much of his knowledge from the infinitesimals of tone, that there was a spice of "It is my duty and I will" in this praiseworthy resolve which fell short of the ecstatic resolution of the Saturday Nora.
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。