corundum

/kəˈɹʌn.dəm/

Meanings

noun

刚玉

An extremely hard mineral, a form of aluminum oxide with the chemical formula Al2O3, that occurs in the form of the gemstones sapphire and ruby; it is used as an abrasive.

Examples :

"Because of its hardness, corundum is used in sandpaper to smooth rough wood. "

由于刚玉非常坚硬，所以常被用于制作砂纸，用来磨平粗糙的木头。

Related Words

gemstones noun

/ˈdʒɛmˌstoʊnz/

宝石，宝玉

"The jewelry box was filled with colorful gemstones like rubies, emeralds, and sapphires. "

那个珠宝盒里装满了色彩鲜艳的宝石，比如红宝石、祖母绿和蓝宝石。

occurs verb

/əˈkɜːz/ /əˈkɝz/

发生，出现。

"The liftoff will occur in exactly twelve seconds."

发射将在十二秒后准时发生。

because adverb

/bɪˈkɒz/ /biˈkɔz/

因为，由于。

"I went to the park because the weather was nice. "

因为天气很好，所以我去了公园。

extremely adverb

/ɪksˈtɹiːmli/

极其，非常。

"The weather was extremely hot today; we stayed inside all afternoon. "

今天天气极其炎热，我们整个下午都待在室内。

abrasive noun

/əˈbɹeɪ.sɪv/

磨料，研磨剂

"The mechanic used an abrasive to smooth the rough edges of the metal pipe. "

那位技工用研磨剂来打磨金属管粗糙的边缘。

aluminum noun

/ə.ˈluː.mɨ.nəm/

铝，铝金属。

"My bicycle's frame is made of aluminum. "

我的自行车的车架是用铝做的。

formula noun

/ˈfɔː.mjʊ.lə/ /ˈfɔɹ.mjə.lə/

公式，方程式

"The formula for calculating the area of a rectangle is length times width. "

计算长方形面积的公式是长乘以宽。

mineral noun

/ˈmɪ.nəɹ.əl/

矿物，矿藏

"The geologist found a beautiful mineral specimen in the rock collection. "

地质学家在岩石收藏中发现了一块漂亮的矿物标本。

hardness noun

/ˈhɑːrdnəs/ /ˈhɑːdnəs/

硬度，坚硬度。

"The hardness of the diamond makes it ideal for cutting glass. "

钻石的硬度使得它非常适合切割玻璃。

sandpaper noun

/ˈsændˌpeɪpɚ/

砂纸，金刚砂纸

"Before painting the walls, she used sandpaper to smooth out the rough spots. "

在粉刷墙壁之前，她用砂纸把粗糙的地方打磨光滑。

chemical noun

/ˈkɛmɪkəl/

化学物质，化学品

"The scientist studied the chemical composition of the soil sample. "

这位科学家研究了土壤样本的化学物质组成。

sapphire noun

/ˈsæf.aɪ̯ə(ɹ)/ /ˈsæf.aɪ̯ɚ/

蓝宝石，青玉。

"My grandmother's necklace featured a beautiful sapphire, reflecting the light beautifully. "

我奶奶的项链上有一颗美丽的蓝宝石，晶莹剔透，能很好地反射光芒。