Definition

1. Noun:
   • Rainbow: A meteorological and optical phenomenon that appears as a multicolored circular arc in the sky. It is caused by the refraction, dispersion, and reflection of sunlight in water droplets, resulting in a spectrum of light. It typically appears opposite the sun.
   • Trajectory (Military): In a specific military context, it refers to a high-angle, arcing trajectory for projectiles, similar to the arc of a rainbow.

Usage Examples

• Noun (Rainbow):
  • Sau cơn mưa, một cái cầu vồng rất đẹp xuất hiện. (After the rain, a very beautiful rainbow appeared.)
  • Bảy sắc của cầu vồng là đỏ, cam, vàng, lục, lam, chàm, tím. (The seven colors of the rainbow are red, orange, yellow, green, blue, indigo, violet.)
• Noun (Trajectory):
  • Pháo binh sử dụng cách bắn cầu vồng để đánh vào mục tiêu phía sau vật che khuất. (Artillery uses high-angle fire to hit targets behind cover.)

Advanced Usage

• The phrase "bắn cầu vồng" is a fixed military term meaning "to fire in a high trajectory" or "to lob shells."
  • Chiến hạm bắn cầu vồng từ ngoài khơi. (The warship lobbed shells from offshore.)

Variants and Related Words

• Cầu vồng khuyết: A partial rainbow that does not form a full arc.
• Cầu vồng kép / Cầu vồng đôi: A double rainbow.

Synonyms

• Rainbow: Spectrum, colored arc.
• Trajectory (for "bắn cầu vồng"): High-angle fire, plunging fire, indirect fire.

Related Idioms and Cultural References

• Chân trời cầu vồng: Rainbow's end (often used metaphorically for an elusive goal or pot of gold).
  • Đi tìm chân trời cầu vồng. (To go searching for the end of the rainbow.)
• Cầu vồng sau mưa: A rainbow after the rain (a common metaphor for hope, beauty, or a positive outcome after a difficult period).
  • Hãy lạc quan, cầu vồng luôn xuất hiện sau cơn mưa. (Be optimistic, the rainbow always appears after the rain.)

noun

1. Rainbow
   • bắn cầu vồng
     to lob shells