# theoretical

/ˌθiɝˈɛtɪkəɫ/ (US) · /θiəɹˈɛtɪkəl/ (UK) · CEFR C1 · Adjective

Source: https://englishreference.com/word/theoretical
Updated: 2026-05-02

## Definition

based on ideas or possibilities rather than on real things you can see or touch. You use this when something is possible in your mind but has not happened in real life yet.

For teachers: relating to or based on a system of ideas rather than practical application. Often used to describe a scenario that is hypothetical or speculative in nature.

## Examples

- The plan is still theoretical and hasn't been tested.
- While the solution works in a theoretical sense, the engineers are worried about how it will perform in extreme weather.
- The physicist presented a theoretical model of the universe that challenged existing laws, though empirical evidence to support his claims remains elusive due to current technological limitations.

## Usage notes

- Commonly used in contrast with 'practical' or 'applied'.

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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.