compounds
compounds — noun
- compoundssingular
- compoundsesplural
1. a substance produced when atoms from multiple chemical elements bond with each o
a substance produced when atoms from multiple chemical elements bond with each other in a set proportion
Elena learned in class that water is a compound made of hydrogen and oxygen.
compound + made of + elements
The lab technician warned that this particular compound can be dangerous when heated.
Salt is a simple compound formed when sodium bonds with chlorine.
compound + formed when + elements bond
Many organic compounds contain carbon atoms arranged in long chains.
- chemical compound
- organic compound
- compound of
- element
a pure substance made of one type of atom, not a combination
Grammar Patterns
compound + of + elements/substances
Common Mistakes
2. something produced by uniting several separate things, such as traits, materials
something produced by uniting several separate things, such as traits, materials, or components, into a single entity
Ryo found that a compound of hard work and talent led to his success.
compound + of + abstract qualities
The new material is a compound of plastic and natural fibers developed by Tunde's team.
Her personality is a curious compound of shyness and fierce determination.
The museum exhibit showed how the building is a compound of several architectural styles.
compound + of + styles/elements
- compound of
- curious compound
- complex compound
- combination
more common and less formal; compound suggests a tighter fusion
- blend
suggests smooth mixing rather than structural combination
- mixture
more general; may imply the parts remain distinguishable
Grammar Patterns
compound + of + nouns
3. a word that is made by joining two or more separate words together, such as 'too
a word that is made by joining two or more separate words together, such as 'toothbrush' or 'mother-in-law'
Nila asked her teacher whether 'firefighter' is a compound or a single word.
compound as linguistic term
English has many compounds like 'snowman', 'notebook', and 'sunglasses'.
Yael explained that 'motherboard' is a compound formed from 'mother' and 'board'.
compound formed from + two words
Saira checked her dictionary and found 'well-being' listed as a hyphenated compound word.
hyphenated compound word
The meaning of a compound like 'greenhouse' is not simply 'green' added to 'house'.
meaning of compound differs from parts
- compound noun
- compound word
- form a compound
- compound noun
more specific; refers to compounds that function as nouns
- portmanteau
a blended word like 'brunch' where parts overlap
- simple word
a word that is not formed from multiple components
Grammar Patterns
compound + noun (modifier)
Usage Note
Compounds may be written as one word (closed), with a hyphen, or as separate words depending on convention. The meaning is often not predictable from the individual parts.
4. a walled or fenced area containing several buildings used for a particular funct
a walled or fenced area containing several buildings used for a particular function, such as a factory, prison, or embassy
The United Nations compound in New York has its own security officers at every gate.
compound as secure area with buildings
Yara walked past the embassy compound on her way to the market every morning.
The research compound contains laboratories, offices, and a small cafeteria for the staff.
Tunde grew up in a large family compound where his cousins lived next door.
family compound as extended-family housing
- embassy compound
- military compound
- family compound
- prison compound
Grammar Patterns
the + compound
compound + has/contains
Usage Note
This sense often refers to secure or restricted areas such as military camps, prison grounds, or diplomatic facilities. It can also describe a traditional extended-family housing arrangement.
Common Mistakes
compounds — verb
- compoundspresent simple I / you / we / they
- compoundses3rd person singular
- compoundsing-ing form
- compoundsedpast simple
1. to increase the seriousness of a problem, negative situation, or harmful effect
to increase the seriousness of a problem, negative situation, or harmful effect
Quan's decision to lie only compounded the problem with his manager.
compound + the problem
Heavy rain compounded the difficulties faced by rescue workers after the earthquake.
Elena's injury was compounded by the fact that she had no medical supplies nearby.
passive: was compounded by
The company's financial troubles were compounded when the bank refused to extend the loan.
Poor planning compounded the team's inability to meet the project deadline.
- compound the problem
- compound the difficulty
- compound the damage
- aggravate
more formal; suggests making something already bad even worse
- exacerbate
formal register; mainly used with medical or social problems
- worsen
more direct and common in everyday speech
Grammar Patterns
compound + noun (problem/issue/difficulty)
Usage Note
Frequently used in formal or serious contexts. The object is typically a negative abstract noun (problem, difficulty, trouble, crisis, injury).
Common Mistakes
2. to combine two or more substances, ingredients, or elements to create a new prod
to combine two or more substances, ingredients, or elements to create a new product or mixture
Jude compounded the herbs with oil to make a traditional healing balm.
compound + noun + with + noun
The pharmacist compounded a special cream for Nila's skin condition.
pharmacist compounds a medicine
This traditional paint is compounded from natural pigments and egg yolk.
passive: is compounded from
Chemists in the laboratory compounded a new type of plastic using plant-based materials.
- compounded from
- compounded with
- compounded by a pharmacist
- separate
to divide into individual parts or elements
Grammar Patterns
compound + noun + with + noun
be compounded of/from
Usage Note
This sense is more technical than the everyday word 'mix'. It is often used in professional contexts like pharmacy, chemistry, or manufacturing.
Common Mistakes
compounds — adjective
- compoundspositive
- more compoundscomparative
- most compoundssuperlative
1. formed by putting together several distinct parts, elements, or ingredients to c
formed by putting together several distinct parts, elements, or ingredients to create a single unified thing
Ilan used 'and' to join two short ideas into a compound sentence for his report.
compound sentence (grammar term)
William examined the compound leaf of the rose bush in his biology class.
The microscope uses a compound lens system to achieve higher magnification.
compound lens / compound microscope
Yara designed a compound exercise that works out both the arms and the legs.
The compound fracture required surgery because the broken bone pierced the skin.
- compound sentence
- compound fracture
- compound eye
- compound interest
- simple
consisting of only one part or element
Grammar Patterns
compound + noun
Usage Note
This adjective appears in many specialized terms across different fields — grammar (compound sentence), botany (compound leaf), medicine (compound fracture), and optics (compound microscope).
2. relating to a financial method where interest payments earn additional interest
relating to a financial method where interest payments earn additional interest on top of the original sum, so the total grows faster over time
Hari opened a savings account that earns compound interest paid monthly by the bank.
compound interest on savings
Nila was surprised how quickly her investment grew thanks to the power of compound returns.
The financial advisor explained that compound growth rewards long-term investors the most.
compound growth / compound returns
Luca compared simple and compound interest to decide which loan offered the better deal.
- compound interest
- compound growth
- compound return
- simple
simple interest is calculated only on the original amount, not on accumulated interest
Grammar Patterns
compound + noun (interest/growth)
Usage Note
Almost exclusively used before the nouns 'interest', 'growth', or 'return'. Compound interest is a core concept in personal finance and investing.
Word family
- compoundverbB2
- compoundadjectiveB2
- compoundingnounC1
- compoundernounC2
Synonym discussion
Sense: noun/1
A 'compound' is a specific type of 'substance' formed by chemically bonding two or more 'elements' in fixed proportions. While all compounds are substances, not all substances are compounds — for example, pure copper is a substance but an element, not a compound. A 'mixture' differs from a compound because its components can be physically separated and are not chemically bonded; salt water is a mixture, whereas salt (NaCl) is a compound. 'Chemical' is a broader everyday term that can refer to any substance with a defined composition, including both elements and compounds. In a lab setting: 'The chemist synthesized a new compound from two elements' describes a chemical reaction; 'The chemist prepared a mixture of powders' describes a simple physical combination.
Common collocations
Phrases
- a compound of
- compounded with
- compound interest
Etymology
The word 'compound' entered English from French 'compoundre', which came from Latin 'componere' — 'com-' meaning 'together' and 'ponere' meaning 'to put'. The original sense was 'to put together', which evolved into both the chemical meaning (putting elements together to form a substance) and the enclosed-area meaning (placing buildings together inside a walled space).
First known use
1530
1530, in the meaning defined at sense 2a Verb