noun (n)

• an arc of colored light in the sky caused by refraction of the sun's rays by rain

  busur dari berwarna terang di langit disebabkan oleh biasan sinar matahari oleh hujan

  source: wordnet30
• an illusory hope

  sebuah khayalan harapan

  Example:
  Chasing rainbows.
  

  source: wordnet30
• A bow or arch exhibiting, in concentric bands, the several colors of the spectrum, and formed in the part of the hemisphere opposite to the sun by the refraction and reflection of the sun's rays in drops of falling rain.

  arch busur atau mengalami, dalam band sepusat, the beberapa warna dari spektrum, dan terbentuk di bahagian seberang belahan bumi ke matahari dengan pembiasan dan refleksi sinar matahari di titik hujan jatuh.

  source: webster1913