Is 'chorion' a common English word?

No, it is a low-frequency technical term used almost exclusively in biological and medical contexts.

Can 'chorion' be used as a verb?

No, 'chorion' is exclusively a noun. The related adjective is 'chorionic'.

What is the difference between the chorion and the amnion?

The chorion is the outermost foetal membrane, while the amnion is the innermost membrane that directly surrounds the embryo.

Do I need to know this word for general English?

No, unless you are studying or working in embryology, reproductive medicine, or a related biological field.

Is “chorion” formal?

Chorion is usually technical/scientific in register.

How do you pronounce “chorion”?

Chorion: in British English it is pronounced /ˈkɔːrɪɒn/, and in American English it is pronounced /ˈkɔːriɑːn/. Tap the audio buttons above to hear it.

chorion: meaning, definition, pronunciation and examples

Low

UK/ˈkɔːrɪɒn/US/ˈkɔːriɑːn/

Technical/Scientific

My Flashcards

Quick answer

What does “chorion” mean?

The outermost membrane surrounding an embryo in reptiles, birds, and mammals.

Audio

Pronunciation

Definition

Meaning and Definition

The outermost membrane surrounding an embryo in reptiles, birds, and mammals.

In insects, the protective shell or membrane surrounding the eggs; in botany, the outer membrane of certain seeds.

Dialectal Variation

British vs American Usage

Differences

No significant differences in meaning or usage between British and American English.

Connotations

Purely technical/medical in both varieties.

Frequency

Equally low frequency in both varieties, confined to specialist literature.

Grammar

How to Use “chorion” in a Sentence

The chorion of [organism]Chorion surrounding [embryo/egg]Chorion derived from [tissue]

Vocabulary

Collocations

strong

chorionic villuschorionic membranechorionic cavitychorionic gonadotropin

medium

outer chorionembryonic chorionfoetal chorion

weak

human chorionthick choriondeveloping chorion

Examples

Examples of “chorion” in a Sentence

adjective

British English

The chorionic tissue was analysed.
Chorionic villus sampling is a prenatal test.

American English

The chorionic tissue was analyzed.
Chorionic villus sampling is a prenatal test.

Usage

Meaning in Context

Business

Not used.

Academic

Used in biology, medicine, and veterinary science textbooks and research papers.

Everyday

Virtually never used.

Technical

Standard term in embryology, reproductive health, and entomology.

Vocabulary

Synonyms of “chorion”

Strong

serosa (in insects)

Neutral

outer membraneembryonic sac

Weak

protective layerenveloping membrane

Vocabulary

Antonyms of “chorion”

amnion (inner membrane)yolk sac

Watch out

Common Mistakes When Using “chorion”

Mispronouncing as 'chor-ee-on' (should be 'kor-ee-on').
Confusing it with 'cornea' or 'chlorine'.
Using it in non-biological contexts.

FAQ

Frequently Asked Questions

: No, it is a low-frequency technical term used almost exclusively in biological and medical contexts.
: No, 'chorion' is exclusively a noun. The related adjective is 'chorionic'.
: The chorion is the outermost foetal membrane, while the amnion is the innermost membrane that directly surrounds the embryo.
: No, unless you are studying or working in embryology, reproductive medicine, or a related biological field.
: The outermost membrane surrounding an embryo in reptiles, birds, and mammals.
: Chorion is usually technical/scientific in register.
: Chorion: in British English it is pronounced /ˈkɔːrɪɒn/, and in American English it is pronounced /ˈkɔːriɑːn/. Tap the audio buttons above to hear it.

Phrases

Idioms & Phrases

“None”

Learning

Memory Aids

Mnemonic

Think 'CHORus' surrounding a singer – the CHORion surrounds the embryo.

Conceptual Metaphor

PROTECTIVE BUBBLE / OUTER SHELL

Practice

Quiz

Fill in the gap

In early pregnancy, the forms the outer boundary of the conceptus.

Multiple Choice

The chorion is primarily associated with which of the following?