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empirical vs. molecular

[em-pir-i-kuhl] / ɛmˈpɪr ɪ kəl /

adjective

  1. derived from or guided by direct experience or by experiment, rather than abstract principles or theory.

    Empirical evidence of changes in kelp consumption was gathered by measuring the bite marks in seaweed fronds.

    Synonyms:
    pragmatic, firsthand, practical
    Antonyms:
    theoretical, secondhand
  2. depending upon experience or observation alone, without using scientific method or theory, and hence sometimes insufficiently authoritative, especially as in medicine.

    That is nothing but an empirical conclusion with no regard for the laws of thermodynamics.

    Synonyms:
    pragmatic, firsthand, practical
    Antonyms:
    theoretical, secondhand
  3. provable or verifiable by experience or experiment, as scientific laws.

    Theoretical physics is criticized for producing complex concepts that are mathematical, not empirical.

[muh-lek-yuh-ler] / məˈlɛk yə lər /

adjective

  1. of or relating to or caused by molecules.

    molecular structure.