noun
tropics; tropical circles
Refers specifically to the Tropic of Cancer (北回帰線) and the Tropic of Capricorn (南回帰線). Used in geography and astronomy.
北回帰線は北緯23度26分に位置する。
The Tropic of Cancer is located at 23 degrees 26 minutes north latitude.
南回帰線より南の地域では、太陽が真上に来ることはない
In regions south of the Tropic of Capricorn, the sun never comes directly overhead.
noun
regression line
Mathematical term for the line that best fits a set of data points in regression analysis.
この散布図に回帰線を引いてください。
Please draw a regression line on this scatter plot.
Specifically the Tropic of Capricorn.
Regression analysis, the statistical method that produces a regression line.
Compound of 回帰 (return, regression) and 線 (line). The geographical sense comes from the sun's apparent 'return' at the solstices; the mathematical sense is a direct translation of the English term 'regression line'.