11 letters · 19 points in Scrabble
noun the region inside the heliopause containing the sun and solar system
originEtymology tree Proto-Indo-European *sóh₂wl̥ Proto-Indo-European *sh₂wél(i)yos Proto-Hellenic *hāwélios Ancient Greek ἥλῐος (hḗlĭos) English helio- Ancient Greek σφαῖρᾰ (sphaîră)bor. Latin sphaera Late Latin sphērader. Old French spherebor. Middle English spere English sphere English -sphere English heliosphere From helio- + -sphere.
Etymology from Wiktionary, CC BY-SA 3.0