portrait

1、a back formation from portraiture.
2、portraiture => portrait.

portrait 肖像，描绘

来自中古法语portrait,肖像，描绘，来自古法语portraire,描绘，描画，-t,过去分词格，词源同portray.

portrait

portrait: [16] Portrait was borrowed from French portrait, which originated as the past participle of the verb portraire ‘depict’ (source of English portray [14]). This was descended from Latin prōtrahere, a compound verb formed from the prefix prō- ‘forth’ and trahere ‘draw’ (source of English tractor). This originally meant ‘draw out, reveal’, and also ‘lengthen’ (it has given English protract [16]), but in medieval Latin it came to be used for ‘depict’.
=> portray, protract, tractor

portrait (n.)

1560s, "a figure, drawn or painted," a back formation from portraiture or directly from Middle French portrait, from Old French portret (13c.), noun use of past participle of portraire "to paint, depict" (see portray). Especially of the head and face of a person.

1. Today his picture goes on show at the National Portrait Gallery.

今天他的画作在国家肖像美术馆展出。

2. He gives us a portrait of the real Gandhi, warts and all.

他向我们描绘了真正的甘地，包括他的不足。

3. "Elizabeth R", a TV portrait of the Queen, had record viewing figures.

关于女王的电视专题片《伊丽莎白女王》创下了收视纪录。

4. Lucian Freud has been asked to paint a portrait of the Queen.

卢西恩·弗洛伊德已受邀为女王画肖像画。

5. Alberg took the portrait down from the wall.

阿尔伯格从墙上摘下那幅肖像画。

【picture, sketch, cartoon, illustration, diagram, painting, portrait, drawing】
这组词都有“画，图”的意思，其区别是：
picture: 指广义的“图画”，现多用来指相片、画像。
sketch: 通常指只画出物体主要特征的图画。
cartoon: 指幽默或讽刺性漫画。
illustration: 指插入书页之间帮助说明的任何插图或图解。
diagram: 多指科技书籍或文献中具有概括解说作用的图表、图样或略图。
painting: 指着色的画。
portrait: 指肖像，只用于指人。
drawing: 指用线条或色彩绘成的图画。