# theoretically

/ˌθiɝˈɛtɪkəɫi/ (US) · /θiəɹˈɛtɪkli/ (UK)

Source: https://englishreference.com/word/theoretically
Updated: 2026-06-20

## Senses

### 1. hypothetically

adverb · CEFR B2

used to say that something could happen or be true, but it has not been proven yet.

For teachers: used to describe a situation that is possible according to a set of rules or assumptions, though it may not be the case in practice.

- Theoretically, the journey should only take two hours, but the traffic is often terrible.
- Theoretically, the new engine design should reduce fuel consumption by twenty percent, though real-world testing has yet to confirm these laboratory results.

Usage: often used at the beginning of a sentence to set a hypothetical frame.

### 2. in a scientific or formal way

adverb · CEFR C1 · Academic · Formal

in a way that relates to the ideas or principles of a subject rather than the practice.

For teachers: in a manner relating to the theory or underlying principles of a specific field of study.

- The students studied the subject theoretically before they started the practical lab work.
- The paper explores the problem theoretically, establishing a mathematical framework before suggesting any specific engineering applications.

Usage: frequently appears in academic writing to distinguish conceptual work from applied work.

## Examples

- The journey should theoretically take three hours.
- Theoretically, the new software can handle thousands of users at once, but we need to test it under pressure.
- While the plan is theoretically sound, the logistics of transporting such heavy equipment across the desert present significant practical challenges that the initial proposal ignored.

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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.