Her wiry hair was pushed up on top of her head in an untidy bun.

她那硬直的头发被向上梳起，在头顶盘成一个乱蓬蓬的髻。

《柯林斯英汉双解大词典》

Hypothyroidism is an underproduction of certain hormones and is the most common cause of patchy hair loss known as alopecia areata (which can affect the whole body and not just the head).

甲状腺功能衰退症就是某种激素分泌较少，这是头发脱落形成斑秃的最常见原因(这可能影响整个身体而不仅仅是头部)。

youdao

And then he kissed her rosy mouth, played with her long waving hair, and laid his head on her heart, while she dreamed of human happiness and an immortal soul.

于是他吻了她鲜红的嘴唇，摸抚着她的长头发、把他的头贴到她的心上，弄得她的这颗心又梦想起人间的幸福和一个不灭的灵魂来。

youdao

He has an unmissable shock of straight white hair, and one afternoon I saw the top of his head moving past the top of my cubicle.

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On the other side of the table from Jung was Lowell Wood, an imposing man with graying red hair and an enormous head.

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