whiten 使變白、變白；美白（如 whitening 美白產品、teeth whitening 牙齒美白）｜字脈

1使變白、變白；美白（如 whitening 美白產品、teeth whitening 牙齒美白）
Verb. To make something , or to become . It works both ways with no change of form: "this whitens teeth" (someone acts on something) and "the sky whitened as the sun rose" (something changes by itself).
Where you meet it most is in beauty and cleaning: whiten your teeth, whiten your clothes, whitening cream, teeth-whitening treatment. In Taiwan and much of Asia, 美白 is a huge market, so 'whitening' is the word all over those English labels.
It is also used of faces and skin losing colour from shock, fear or cold: "his face whitened when he heard the news". This is a bit literary; in ordinary speech people say went white or turned pale.
A note on which word to choose. English usually prefers turn white or go white for something changing on its own — "her hair turned white", not usually "her hair whitened". Whiten sounds most natural when someone does it on purpose to something, or in writing. And be careful with people: to whiten skin is a loaded phrase, tied to real and painful history about skin colour, so in most conversations use lighten or brighten instead unless you mean the cosmetic product.

組成white + -en。-en 是造動詞的字尾，意思是「使成為…／變成…」，接在形容詞後面。

原始詞典資料4 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。

Whitenname

whitenverb/ˈ(h)waɪ̯.tən/

1
(To cause) to become white or whiter; to bleach or blanch.
- Age had whitened his hair.
- The trees in spring whiten with blossoms.
2
computingcryptographyengineeringTo increase the security of an iterated block cipher by steps that combine the data with portions of the key.
3
mathematicssciencesstatisticsTo normalize data so that the covariance matrix becomes the identity matrix; i.e., to remove correlations so each variable has unit variance.

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。