円錐（えんすい、ensui）
- cone

The Japanese word 円錐 (えんすい, *ensui*) refers to a cone. It's a three-dimensional geometric shape that tapers smoothly from a flat base (usually circular) to a point called the apex or vertex. The base can be any shape, but commonly it is a circle. The sides of a cone are curved and meet at the apex. This is often used in mathematics and in everyday life to describe the shape.

⚫︎アイスクリームは円錐の形をしている。 Translation: The ice cream is cone-shaped. ⚫︎あの建物は円錐型の屋根を持っています。 Translation: That building has a cone-shaped roof. ⚫︎数学の授業で、円錐の体積を計算しました。 Translation: We calculated the volume of a cone in the math class.

This word is used when you want to describe something that has the shape of a cone or when you're talking about cones in a mathematical context. It can be used in conversations about geometry, architecture, food, and other things. For example, you might use it when describing a traffic cone, the shape of a volcano, or a party hat.

The word is typically written in kanji as 円錐 (*ensui*). The reading is えんすい in hiragana. There are no other common ways to write this word, nor are there variations in okurigana. The word itself is 円錐.

There aren't direct synonyms for 円錐 that specify the same geometric shape. However, words related to shape might be used: ⚫︎ 円錐形 (*ensuikei*): Cone shape.

There aren't direct antonyms for the word 円錐 in terms of shape. However, in mathematics, one might compare it with different shapes. Here are some examples: ⚫︎立方体 (*rippoutai*): Cube ⚫︎球 (*kyuu*): Sphere

そのケーキはチョコレートでコーティングされた円錐形だった。 ・Translation: The cake was cone-shaped, coated in chocolate. ・Explanation: This sentence describes the shape of the cake using the word 円錐形 (cone shape).

円錐の体積を求める公式を覚えていますか？ ・Translation: Do you remember the formula to find the volume of a cone? ・Explanation: This sentence uses the word 円錐 in the context of a mathematical formula.

The word 円錐 is a compound word. 円 (*en*) means "circle" and 錐 (*sui*) means "awl" or a pointed tool for piercing. So, 円錐 conceptually means "circle awl" which aptly describes the shape's features. It's a direct borrowing from Chinese, where the meaning and composition are similar.