incandescent (adj.)

1794, from French incandescent (18c.) or directly from Latin incandescentem (nominative incandescens), present participle of incandescere "become warm, glow, kindle," from in- "within" (from PIE root *en "in") + candescere "begin to glow, become white," inceptive of candere "to glow, to shine" (from PIE root *kand- "to shine"). In reference to electric light, from 1881. The verb incandesce (1838), originally in science, is perhaps a back-formation.