atom

atom — noun

1. the basic unit in chemistry that keeps the character of one element and may join

1.名詞B2
釋義

the basic unit in chemistry that keeps the character of one element and may join to other units

例句

A hydrogen atom has only one electron around its center.

pattern: an atom of [element]

In the model, each carbon atom touched four small white balls.

collocation: carbon atom

同義詞
  • particle

    broader scientific word that can refer to many kinds of very small pieces

  • unit

    very general and does not specifically suggest chemistry

  • building block

    an explanatory phrase rather than a precise scientific term

文法句型

an atom of hydrogen

atoms combine to form molecules

an atom loses an electron

用法筆記

Common in chemistry and physics. Distinguish from noun/2 TINY AMOUNT, which means a very small piece or quantity. Also distinguish atom from molecule: a molecule is made from two or more atoms joined together.

常見錯誤

Water has three atoms in one atom.
Water has three atoms in one molecule.
💡an atom is one unit of an element; a molecule is a group of atoms joined together.

2. a very small piece or amount of something

2.名詞
釋義

a very small piece or amount of something

例句

There was not an atom of sugar left in the tea.

not an atom of + noun

Without an atom of shame, the thief asked for more money.

without an atom of + abstract noun

同義詞
  • bit

    the most general everyday word for a small amount or piece

  • speck

    usually a tiny visible mark or grain, especially of dust or dirt

  • trace

    often means a very small amount that is just enough to notice

  • particle

    can sound more scientific or formal than everyday bit

文法句型

an atom of dust

not an atom of pity

every atom of something

用法筆記

Usually appears with of, especially in phrases such as not an atom of, without an atom of, or every atom of. It is much less common than ordinary words like bit, speck, or trace.

常見錯誤

There wasn't atom of milk in the cup.
There wasn't an atom of milk in the cup.
💡use an before atom in this pattern.