Combination vs Compound vs Fusion

When to use each in English, with meaning, register, and examples.

Combination

Top 2,000 (common)B2noun

Compound

Top 2,000 (common)B2noun

Fusion

Top 5,000 (fairly common)
 CombinationCompoundFusion
Pronunciation🇬🇧 /["/ˌkɒmbɪˈneɪʃn/"]/🇺🇸 /["/ˌkɑːmbɪˈneɪʃn/"]/🇬🇧 /["/ˈkɒmpaʊnd/"]/🇺🇸 /["/ˈkɑːmpaʊnd/"]/🇬🇧 //ˈfjuːʒən//🇺🇸 //ˈfjuːʒən//
MeaningA mix of different things together.A substance made of two or more elements joined together.The process of combining two or more things into one.
ExampleThe combination of colors in her painting is truly remarkable.A compound is formed when two or more elements are chemically bonded together.The fusion of cultures can lead to unique art forms.
RegisterNeutralNeutralNeutral
How commonTop 2,000 (common)Top 2,000 (common)Top 5,000 (fairly common)
CEFR levelB2B2-
Part of speechnounnoun
Collocationsideal, perfect, right, in combination (with), combination of, ideal, perfect, right, in combination (with), combination ofchemical, inorganic, organic, form, make, produce, contain something, be derived from something, be found in something, compound of, military, palace, prison, in a/​the compound, inside a/​the compoundnuclear fusion, cultural fusion, cuisine fusion, fusion energy, fusion music
Antonymsseparation, divisionelement, simple substance-
Common mistakesConfused with 'combine' as a verb., 'Combination' used as a verb instead of a noun., Misplacing the stress on the wrong syllable: 'COM-bin-a-tion' instead of 'com-BI-na-tion'.Confused with 'composite' – remember 'compound' refers to specific chemical substances., Using 'compound' for non-chemical mixtures – be clear it refers to combinations of elements.Confused with 'fission', which means splitting instead of combining., Used incorrectly as a verb, 'to fusion'., Omitting context, leading to vagueness in meaning.
Usage notesUsed in both formal and informal contexts. Commonly seen in discussions about recipes, math, and combinations of different concepts. Avoid in casual conversations when a simpler word like 'mix' would suffice.Use 'compound' in scientific contexts, especially in chemistry. Avoid in everyday conversation unless explaining scientific concepts.Used in scientific contexts, such as physics and biology, but can also refer to cultural or culinary combinations. Avoid in overly casual conversations.

Frequently asked questions: Combination vs Compound vs Fusion

What's the difference between Combination, Compound, and Fusion?

Combination: A mix of different things together. Compound: A substance made of two or more elements joined together. Fusion: The process of combining two or more things into one.

Can I use Combination, Compound, and Fusion interchangeably?

Not always. Combination, Compound, and Fusion are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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