The verb is probably derived partly: * from Middle English alighten (“to kindle, light, set on fire; to begin burning; to become bright, shine; to arouse, rouse, stir; (figuratively) to enlighten spiritually, illuminate”) [and other forms], from Old English ālīhtan, ālȳhtan (“to light up; enlighten”) (perhaps modelled after Latin illūmināre, the present active infinitive of illūminō (“to brighten, illuminate, light up”)), from ā- (prefix meaning ‘away, from, off, out’) + līhtan, līehtan (“to glow, to shine; to illuminate, to light”) (ultimately from Proto-Indo-European *lewk- (“to see; to shine; bright”)); and * from Middle English onlighten (“to cause (something) to shine; to clarify; (figuratively) to enlighten spiritually”) [and other forms], from Old English onlīhtan, a variant of inlīhtan (“to give light to, brighten, illuminate; to cause to shine; to shine; (figuratively) to give clear sight; to clear a mental fog, enlighten”), from Proto-Germanic *inliuhtijaną (“to enlighten, illumine”), from *in (“in; into”) + *liuhtijaną (“to give light, shine”) (ultimately from Proto-Indo-European *lewk-; see above); and * from later uses of alight (adjective). The English word is analysable as a- (prefix meaning ‘away, from, off, out’) + light (“to start (a fire); to burn, set fire to; to become ignited, take fire; to provide light, illuminate; to show the way by means of a light”). The adjective and adverb are derived from Late Middle English alight (adjective) [and other forms], from Old English ālīht, ālȳht, a past participle form of Old English ālīhtan, ālȳhtan (verb) (see above); but have also been subsequently interpreted as a- (prefix meaning ‘at; in; on’, used to show a condition, manner, or state) + light (“not dark or obscure, bright, clear; highly luminous”). Cognates * German erleuchten (“to light up, illuminate”)

aglow • alighten • beamful • beamsome • beamy • belight • beshine • bright • brilliant • debark • disembark • effulgent • enlighten • fire • get off • get off the plane/ship • get out • glowing • illume • illuminate • illuminating • illumine • illustrate • irradiate • lambent • leave the plane/ship • light • light up • lighted • lighten • lit • lucent • luciferous • lucific • luminant • luminiferous • luminous • luster • lustrate • lustrous • orient • profulgent