ENGLISH
REFERENCE

theoretically

adv.
US //ˌθiɝˈɛtɪkəɫi// UK //θiəɹˈɛtɪkli// the·o·ret·i·cal·ly
  1. 1 hypothetically (adv.)
    B2 Upper Intermediate

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

    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.

    Example

    Theoretically, the journey should only take two hours, but the traffic is often terrible.

    Example

    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. 2 in a scientific or formal way (adv.)
    C1 Advanced Academic Formal

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

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

    Example

    The students studied the subject theoretically before they started the practical lab work.

    Example

    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.
Origin

From theoretical + -ly.

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