Definition

1. Noun:
   • Octagon: A flat shape with eight straight sides and eight angles.
   • Octagonal shape: The quality or form of having eight sides and eight angles.

Usage Examples

• Noun:
  • Hình bát giác thường được dùng trong thiết kế. (The octagon is often used in design.)
  • Cô ấy vẽ một bát giác hoàn hảo. (She drew a perfect octagon.)
  • Đây là một tấm gương bát giác. (This is an octagonal mirror.)

Advanced Usage

• "the bát giác": Can be used to refer to a specific octagon shape in a formal or geometric context.
  • Bát giác trong hình học có tổng các góc trong bằng 1080 độ. (The octagon in geometry has internal angles summing to 1080 degrees.)

Variants and Related Words

• Bát diện (noun): Octahedron (a three-dimensional shape with eight faces).
  • Kim cương thường có cấu trúc tinh thể dạng bát diện. (Diamonds often have an octahedral crystal structure.)
• Hình bát giác (noun phrase): Octagonal shape. (This is a compound phrase where "bát giác" is the core noun modified by "hình").
• Có hình bát giác (adjective phrase): Octagonal, having an octagon shape.

Synonyms

• Hình tám cạnh: Eight-sided shape. (A descriptive synonym).
• Khối tám mặt: Eight-faced solid (refers to 3D, not a direct synonym for the 2D shape).

Notes on Meaning

• Geometry: In mathematics, "bát giác" strictly refers to a two-dimensional polygon.
• Architecture & Design: The term is commonly used to describe the floor plan, layout, or cross-section of buildings, rooms, tiles, etc.
  • Tháp chuông có mặt cắt ngang hình bát giác. (The bell tower has an octagonal cross-section.)

noun

1. Octagon, octagonal shape
   • toà nhà bát giác
     octagonal building