14世紀晚期，“寬度”，來自古法語 latitude（13世紀）和直接源自拉丁語 latitudo “寬度，寬度，範圍，大小”，來自 lātus（形容詞）“寬，廣，廣泛”的古拉丁語 stlatus，源自 PIE *stleto-，是 *stele- “擴散，擴展”的後綴形式（源頭還包括古教會斯拉夫語 steljo “展開”，亞美尼亞語 lain “寬”）。
地理和天文學意義也來自14世紀晚期，字面意思是已知世界地圖的“寬度”。比喻意義上的“允許的變化程度，偏離標準的範圍”早在15世紀就出現了。相關詞彙： Latitudinal “與地理緯度有關的”（1777）； latitudinous “解釋寬泛的”（1829，美國英語）。
The ancients supposed the torrid and the frigid zones to be uninhabitable and even impenetrable by man, but while the earth, as known to them, was bounded westwardly by the Atlantic Ocean, it extended indefinitely towards the east. The dimensions of the habitable world then (and ancient geography embraced only the home of man ....,) were much greater, measured from west to east, than from south to north. Accordingly, early geographers called the greater dimension, or the east and west line, the length, longitudo, of the earth, the shorter dimension, or the north and south line, they denominated its breadth, latitudo. These Latin terms are retained in the modern geography of most European nations, but with a modified meaning. [George P. Marsh, "Lectures on the English Language," 1882]
古人認爲熱帶和寒帶是不適宜居住的，甚至是人類無法穿越的，但當他們所知道的地球向西被大西洋所限制時，它向東無限延伸。因此，早期地理學家稱更大的尺寸或東西線爲地球的 length，長度，較短的尺寸或南北線則稱爲 breadth，寬度。這些拉丁術語在大多數歐洲國家的現代地理學中仍然保留，但含義有所改變。[喬治·P·馬什，“英語語言講座”，1882年]
