alighten vs twilight

alighten

verb
  • To make light; to illuminate or brighten. 

  • To lighten; to reduce in weight or heaviness. 

  • To alight, to dismount or get down from. 

  • To alight; to land, to descend and rest. 

twilight

verb
  • To illuminate faintly. 

adj
  • Pertaining to or resembling twilight; faintly illuminated; obscure. 

noun
  • Any faint light through which something is seen; an in-between or fading condition. 

  • The soft light in the sky seen before the rising and (especially) after the setting of the sun, occasioned by the illumination of the earth’s atmosphere by the direct rays of the sun and their reflection on the earth. 

  • The time when this light is visible; the period between daylight and darkness. 

  • The time when the sun is less than 18° below the horizon. 

How often have the words alighten and twilight occurred in a corpus of books? (source: Google Ngram Viewer )