# abstract class

CEFR C1 · Compound

Source: https://englishreference.com/word/abstract-class
Updated: 2026-07-22

## Definition

a blueprint for other objects in computer programming that cannot be used on its own. It defines general features that other, more specific groups must include.

For teachers: a base class in object-oriented programming that cannot be instantiated directly and is intended to be subclassed. It typically contains one or more virtual methods that must be implemented by derived classes.

## Examples

- You cannot create an object directly from an abstract class.
- The developer defined 'Shape' as an abstract class so that specific types like 'Circle' and 'Square' would all share the same basic properties.
- By utilizing an abstract class, the software architecture ensures that all subclasses adhere to a specific interface while preventing the instantiation of an incomplete or overly generic object.

## Pitfalls

- Not "new AbstractClass()" but "new ConcreteSubclass()" — Learners often try to instantiate an abstract class directly, which causes a compiler error because it is only a template.

## Usage notes

- In technical contexts, it is often used with the verbs 'define', 'inherit from', or 'extend'.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.