atom
Atom (noun) means the smallest unit of a chemical element that retains its properties, made up of a nucleus and surrounding electrons. Example: “Every atom of oxygen has eight protons.”
How to Use Atom
Learner’s notesIn plain EnglishThe basic building block of matter — or, informally, the tiniest possible amount of something.
Word Forms
atoms plural
Fill the Gap
Can you complete this real example?
Every _____ of oxygen has eight protons.
Etymology
From Latin atomus, from Greek atomos ("indivisible"), from a- ("not") + temno ("to cut"). Ancient philosophers imagined atoms as the smallest possible pieces of matter, though we now know atoms themselves are divisible.
Frequently Asked Questions
What does “atom” mean?
The word “atom” means the smallest unit of a chemical element that retains its properties, made up of a nucleus and surrounding electrons. In plain terms, the basic building block of matter — or, informally, the tiniest possible amount of something.
How do you pronounce “atom”?
“Atom” is pronounced A-tuhm ([ˈæɾm̩] in IPA).
How do you use “atom” in a sentence?
Here is “atom” used in a sentence: “Every atom of oxygen has eight protons.”
What part of speech is “atom”?
“Atom” is a noun.
Where does the word “atom” come from?
The word “atom” comes from Latin. From Latin atomus, from Greek atomos ("indivisible"), from a- ("not") + temno ("to cut"). Ancient philosophers imagined atoms as the smallest possible pieces of matter, though we now know atoms themselves are divisible.
Is “atom” a common word?
“Atom” is an uncommon word in modern English, usually learned at around the A2 level.
How many meanings does “atom” have?
“Atom” has 2 distinct senses listed in this dictionary. The most common is: the smallest unit of a chemical element that retains its properties, made up of a nucleus and surrounding electrons.