英语词源字典 - 在线词源网站

solar [solar 词源字典]: solar: [15] Solar comes from Latin sōlāris, a derivative of sōl ‘sun’. This went back to the same ultimate Indo-European base, *su-, that produced English sun. Solarium [19] was borrowed from another Latin derivative, sōlārium, which denoted a ‘sundial’ as well as a ‘balcony, flat rooftop, or other part of a house exposed to the sun’. Solstice [13] means etymologically the ‘sun standing still’. It comes from Latin sōlstitium, a compound formed from sōl and stit-, the past participial stem of sistere ‘make stand’.
=> solarium, solstice[solar etymology, solar origin, 英语词源]
roof-top (n.): also rooftop, 1610s, from roof (n.) + top (n.1).