noun

CSS

SEE-ess-ESS

CSS (noun) means a language used to describe how a web page should look — its colours, fonts, spacing, sizes and layout — kept separate from the page's content. Example: “The text was all there, but the CSS had not loaded, so the page looked like a plain list of links.”

noun

technical A language used to describe how a web page should look — its colours, fonts, spacing, sizes and layout — kept separate from the page's content.

"The text was all there, but the CSS had not loaded, so the page looked like a plain list of links."

"She changed one line of CSS and the whole site switched to dark mode."

technical, medicine In medicine, cytokine storm syndrome: a severe reaction in which the immune system releases signalling proteins far too aggressively.

"The paper used CSS throughout to mean cytokine storm syndrome."

How to Use CSS

Learner’s notes

In plain EnglishCSS is the part of a website that decides how everything looks.

When to use it

Almost always written as the initialism; the full form "cascading style sheets" appears mainly in specifications and teaching material. Used as an uncountable noun: "some CSS", not "a CSS".

Memory tip

CSS is a stylesheet language, not a programming language and not a piece of software. It has no logic of its own — it is a set of rules saying which elements should be styled and how.

Trace the full origin ↓

Easily confused with

HTML → JavaScript → SCSS Sass →

Common pairings

write CSS CSS file inline CSS CSS rule CSS framework pure CSS

Study it as flashcards or scroll it in Flow — saved to your collection.

Test yourself on “CSS” A quick quiz — meaning, synonyms & usage →

Fill the Gap

Can you complete this real example?

The text was all there, but the _____ had not loaded, so the page looked like a plain list of links.

Etymology

An initialism of cascading style sheets, so called because style rules from several sources cascade together, with defined rules of precedence deciding which one applies.

Origin: English

Synonyms

View more →

cascading style sheets stylesheet language style sheet

Frequently Asked Questions

What is the difference between CSS and HTML?

HTML sets out what is on the page — headings, paragraphs, images, links — and CSS sets out how those things look. You can view a page with HTML and no CSS and still read everything, it will simply be unstyled. The two are used together on virtually every web page.

Is CSS a programming language?

No. CSS is a stylesheet language: it declares how elements should be presented, rather than describing steps for a computer to carry out. It does have custom properties, which work as variables, and functions such as calc(), but it has no loops and no general branching logic, so it cannot express an algorithm the way a programming language can.

What does the "cascading" in CSS mean?

Style rules can come from several places at once — the browser's own defaults, the site's stylesheets, and rules attached directly to an element. When two rules conflict, the cascade is the set of rules that decides which one wins.

Example Sentences

Real-world examples showing CSS in context, drawn from published sources. Any opinions expressed are those of the original source and do not reflect the views of FreeDict.com.

The quickest way to learn CSS is to take apart a site you admire and see which rules are doing the work.

From CSS Creme

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