English Reference
verb

assume

v.
US /əˈsum/ UK /ɐsˈuːm/ as·sume UK spelling assumes

  1. 01 B1 Intermediate

    to think that something is true, even though you do not have certain proof.

    to accept something as true or as certain to happen, even without proof or formal verification.

    Simple

    I assumed you were coming to the party because I saw your name on the list.

    In context

    Psychologists often assume that early childhood experiences significantly shape adult personality, though this premise is frequently debated in modern research.

    Pitfall
    I assumed about his arrival. I assumed he had arrived.

    The verb 'assume' usually takes a 'that' clause or a direct object, not the preposition 'about'.

  2. 02 B2 Upper Intermediate Formal

    to begin to have a particular job, responsibility, or power.

    to take on or begin to exercise a role, duty, or responsibility. Transitive; requires a direct object.

    Simple

    The vice president will assume the role of director starting next month.

    In context

    Upon the sudden resignation of the CEO, the chief operating officer was forced to assume full control of the company's daily operations.

  3. 03 C1 Advanced LiteraryAcademic

    to start to have a particular quality, look, or way of behaving.

    to take on a particular quality, appearance, or characteristic, often one that is not natural or permanent.

    Simple

    The problem assumed a new importance after the latest news report.

    In context

    As the sun began to set, the desert landscape assumed a deep purple hue that made navigation difficult for the returning scouts.

  4. 04 C2 Proficiency FormalLiterary

    to pretend to have a feeling or a way of behaving that is not real.

    to adopt a feigned quality or manner, often to deceive others.

    Simple

    He assumed an air of confidence to hide how nervous he actually felt.

    In context

    The spy assumed a false identity, complete with forged documents and a convincing backstory, to infiltrate the high-security facility.

Usage approach assume · assume existence · assume importance

It makes sense to assume a teen is using a chatbot because this is most likely the case.

Phys.org· 13 Aug 2026

But it offers a warning against assuming that a small fee will have a small effect.

BBC News· 16 Aug 2026

From Latin assūmō (“accept, take”), from ad- (“to, towards, at”) + sūmō (“take up, assume”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Latin assūmō
Level B2 · Upper Intermediate
Frequency Common
Updated