名詞 wan:

1. a computer network that spans a wider area than does a local area network
   同義詞：wide area network

動詞 wan:

1. become pale and sickly

形容詞 wan:

1. (of light) lacking in intensity or brightness; dim or feeble
   同義詞：pale, pallid, sick
2. abnormally deficient in color as suggesting physical or emotional distress
   同義詞：pale, pallid
3. lacking vitality as from weariness or illness or unhappiness

1. Her face wan after her long illness.
   她久病后臉色變得蒼白。
2. A wan expression.
   慘淡的表情
3. The child looked pale and wan.
   這孩子看上去臉色不好，一副有病的樣子。

wan

adj.（形容詞）
wan.ner,wan.nest
Unnaturally pale, as from physical or emotional distress.
蒼白的：由于身體或精神不適等而致的病態(tài)的蒼白
Suggestive or indicative of weariness, illness, or unhappiness; melancholy:
慘淡的：指示疲勞、疾病或郁悶之象的；郁郁寡歡的：
例句：
a wan expression.
慘淡的表情

v.intr.（不及物動詞）
wanned,wan.ning,wans
To become pale.
變蒼白

來源：
Middle English [pale, gloomy]
中古英語 [蒼白的，陰暗的]
from Old English wann [gloomy, dark]
源自 古英語 wann [陰暗的，黑的]

【引伸】
wan.ly
adv.（副詞）
wan.ness
n.（名詞）