rainbow rainbow /ˈreɪnˌboʊ/

noun

1. () An arc of colored light in the sky caused by refraction of the sun's rays by rain  ( rainbow )
   an arc of colored light in the sky caused by refraction of the sun's rays by rain
    The rainbow was a beautiful sight, with its vibrant colors arching across the sky
   The rainbow was a beautiful sight, with its vibrant colors arching across the sky
   
   
2. An illusory hope  ( rainbow )
   an illusory hope
    Chasing rainbows
   chasing rainbows
   
   

 Bewick's swan Bewick's swan /ˈbjuːɪks swɒn/

noun

1. Eurasian subspecies of tundra swan; smaller than the whooper  ( Bewick's swan , Cygnus columbianus bewickii )
   Eurasian subspecies of tundra swan; smaller than the whooper
   
   

 hymen hymen /ˈhaɪmən/

noun

1. A fold of tissue that partly covers the entrance to the vagina of a virgin  ( hymen , maidenhead , virginal membrane )
   a fold of tissue that partly covers the entrance to the vagina of a virgin
   
   

 Hymen

1. (Greek mythology) the god of marriage  ( Hymen )
   (Greek mythology) the god of marriage
    The celebration reached its climax when they honored Hymen, the god of marriage.
   The celebration reached its climax when they honored Hymen, the god of marriage.
   
   

 endometriosis endometriosis /ˌɛndoʊˌmɛtriːˈoʊsɪs/

noun

1. The presence of endometrium elsewhere than in the lining of the uterus; causes premenstrual pain and dysmenorrhea  ( adenomyosis , endometriosis )
   the presence of endometrium elsewhere than in the lining of the uterus; causes premenstrual pain and dysmenorrhea