noun
Common
ion
EYE-uhn
Ion (noun) means an atom or molecule that has gained or lost electrons, giving it an electric charge. Example: “A positive ion forms when an atom loses one of its electrons.”
noun
1
An atom or molecule that has gained or lost electrons, giving it an electric charge.
"A positive ion forms when an atom loses one of its electrons."
"The air cleaner releases negative ions that attach to tiny particles of dust."
"Salt dissolves in water into sodium and chloride ions."
How to use ion
Learner’s notesIn plain EnglishA charged particle formed when an atom gains or loses electrons.
Common pairings
positive ion
negative ion
ion exchange
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Word forms
- Plural
- ions
Fill the gap
Can you complete this real example?
A positive _____ forms when an atom loses one of its electrons.
Etymology
Coined in 1834 from Greek ion, "going," the present participle of eimi ("I go") — chosen because ions move toward oppositely charged electrodes.
Class of 1834
ion joined the language around 1834.
See the full Class of 1834 →
Synonyms
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charged particle
Rhymes for ion
region
ablation
allusion
emulsion
ideation
novation
diffusion
elocution
extension
oxidation
perfusion
selection
See all rhymes for ion →
Frequently asked questions
What does “ion” mean?
The word “ion” means an atom or molecule that has gained or lost electrons, giving it an electric charge. In plain terms, a charged particle formed when an atom gains or loses electrons.
How do you pronounce “ion”?
“Ion” is pronounced EYE-uhn (/ˈaɪ.ɑn/ in IPA).
How do you use “ion” in a sentence?
Here is “ion” used in a sentence: “Salt dissolves in water into sodium and chloride ions.”
What part of speech is “ion”?
“Ion” is a noun.
Where does the word “ion” come from?
The word “ion” dates back to around 1834 and comes from Greek. Coined in 1834 from Greek ion, "going," the present participle of eimi ("I go") — chosen because ions move toward oppositely charged electrodes.
Is “ion” a common word?
“Ion” is a fairly common word in modern English.
What is the difference between an ion and an atom?
An atom is electrically neutral because it has equal numbers of protons and electrons, while an ion is an atom or molecule that has gained or lost electrons, giving it an overall electric charge. In short, an ion is a charged atom or molecule.
What is the difference between a cation and an anion?
Both are types of ion. A cation carries a positive charge because it has lost electrons, while an anion carries a negative charge because it has gained electrons.
What is the difference between an ion and a molecule?
A molecule is a group of atoms bonded together and is usually electrically neutral, while an ion is any atom or molecule carrying an electric charge. A charged molecule is called a molecular or polyatomic ion.
How does an atom become an ion?
An atom becomes an ion when it gains or loses one or more electrons. Losing electrons leaves it with a positive charge, while gaining electrons gives it a negative charge.
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