English Reference
adjective · noun

atomic

adj. · n.
US /əˈtɑmɪk/ UK /ɐtˈɒmɪk/ atom·ic

  1. 01 B2 Upper Intermediate Technical Science

    adj.relating to atoms, which are the tiny building blocks of everything in the universe.

    adj.pertaining to or consisting of atoms; relating to the structure and properties of the smallest units of a chemical element.

    Simple

    Scientists use special microscopes to study the atomic structure of different metals.

    In context

    The researchers mapped the atomic arrangement of the crystal lattice to understand why the material became brittle at low temperatures.

  2. 02 B2 Upper Intermediate Science

    adj.using or relating to the energy produced by splitting atoms.

    adj.relating to or using energy derived from nuclear fission or fusion.

    Simple

    The country decided to invest more in atomic power to reduce its carbon emissions.

    In context

    The mid-twentieth century saw a rapid expansion of atomic research as nations raced to harness the power of the nucleus for both energy and weaponry.

  3. 03 C1 Advanced Academic

    adj.describing something that is a single unit and cannot be broken down into smaller parts.

    adj.forming a single, irreducible unit; incapable of being split or divided into smaller components.

    Simple

    In this theory, the individual is seen as the atomic unit of society.

    In context

    The philosopher argued that certain basic truths are atomic, meaning they cannot be explained by breaking them down into simpler concepts.

  4. 04 C1 Advanced Technical Computing

    adj.in computer programming, an action that happens completely or not at all, with no middle state.

    adj.referring to an operation that appears to be instantaneous to the rest of the system; it either completes entirely or fails with no partial effect.

    Simple

    The database update must be atomic so that no data is lost if the power goes out.

    In context

    To prevent data corruption during concurrent access, the developer implemented an atomic transaction that locks the record until the update is finalised.

    uninterruptible
  5. 05 C2 Proficiency Technical Computing

    n.a single task in a computer program that cannot be interrupted.

    n.a discrete, uninterruptible operation within a multi-threaded or distributed computing environment.

    Simple

    The system handles each atomic with high priority to ensure the software stays stable.

    In context

    The architecture relies on a series of atomics to manage state changes across the cluster without requiring a central coordinator.

Usage atomic nuclei

A younger voice might look at our atomic weapons and shake its head, predicting that we’ll finish ourselves off.

The Guardian· 23 Aug 2026

The technique gives scientists a way to examine extremely fast chemical reactions at the atomic scale and in real time.

ScienceDaily· 30 Jul 2026

Etymology tree Proto-Indo-European *né Proto-Indo-European *n̥- Proto-Hellenic *ə- Ancient Greek ἀ- (a-) Proto-Indo-European *temh₁- Proto-Indo-European *-né- Ancient Greek τέμνω (témnō) Proto-Indo-European *-ós Proto-Hellenic *-ós ▲ Ancient Greek -ος (-os)influ. Ancient Greek -ός (-ós) Ancient Greek τομός (tomós) Ancient Greek ἄτομος (átomos)bor. Latin atomusbor. Middle French athomebor. Middle English attome English atom Proto-Indo-European *-kos Proto-Italic *-kos Latin -cus Latin -icuslbor. Old French -iquebor. Middle English -ik English -ic ▲ New Latin atomus ▲ New Latin -icus New Latin atomicusbor. English atomic From atom + -ic, or borrowed from New Latin atomicus. Probably also a calque of French atomique.

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

This entry
Level B2 · Upper Intermediate
Frequency Frequent
Updated