of a car, by 1957, from sun (n.) + roof (n.). Originally on European models.
Entries linking to sunroof
sun n.
Old English sunne "the sun," from Proto-Germanic *sunno (source also of Old Norse, Old Saxon, Old High German sunna, Middle Dutch sonne, Dutch zon, German Sonne, Gothic sunno "the sun"), from PIE *s(u)wen-, alternative form of root *sawel- "the sun."
Old English sunne was feminine (as generally in Germanic), and the fem. pronoun was used in English until 16c.; since then masc. has prevailed. The empire on which the sun never sets (1630) originally was the Spanish, later the British. To have one's place in the sun (1680s) is from Pascal's "Pensées"; the German imperial foreign policy sense (1897) is from a speech by von Bülow.
roof n.
"outer upper covering of a house or other building," Middle English rof, from Old English hrof "roof," also "ceiling," hence figuratively "highest point, top, summit" also "heaven, the sky;" from Proto-Germanic *khrofam (source also of Old Frisian rhoof "roof," Middle Dutch roof, rouf "cover, roof," Dutch roef "deckhouse, cabin, coffin-lid," Middle High German rof "penthouse," Old Norse hrof "boat shed").
No apparent connections outside Germanic. "English alone has retained the word in a general sense, for which the other languages use forms corresponding to OE. þæc thatch" [OED]. Meaning "top of a carriage, etc." is by 1706. The meaning "upper part of the mouth, the hard palate" was in late Old English (hrof ðæs muðes). To raise the roof "create an uproar" is attested from 1860, originally in U.S. Southern dialect.