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adjective tox·ic \ˈtäk-sik\

: containing poisonous substances

Full Definition of TOXIC

:  containing or being poisonous material especially when capable of causing death or serious debilitation <toxic waste> <a toxic radioactive gas> <an insecticide highly toxic to birds>
:  exhibiting symptoms of infection or toxicosis <the patient became toxic two days later>
:  extremely harsh, malicious, or harmful <toxic sarcasm>
:  relating to or being an asset that has lost so much value that it cannot be sold on the market
tox·ic·i·ty \täk-ˈsi-sə-tē\ noun

Examples of TOXIC

  1. The fumes from that chemical are highly toxic.
  2. Tests will be run to determine if the landfill is toxic.

Origin of TOXIC

Late Latin toxicus, from Latin toxicum poison, from Greek toxikon arrow poison, from neuter of toxikos of a bow, from toxon bow, arrow
First Known Use: 1664

Other Biology Terms

autochthonous, fecund, homunculus, phylogeny, substrate



Definition of TOXIC

:  a toxic substance —usually used in plural

Examples of TOXIC

  1. <tested for toxics in the water supply>

First Known Use of TOXIC

TOXICITY Defined for Kids


adjective tox·ic \ˈtäk-sik\

Definition of TOXIC for Kids

:  containing, being, or caused by poisonous or dangerous material <toxic waste> <toxic effects>

Word History of TOXIC

Sometimes people put poison on the points of arrows. Even a slight wound from such an arrow can be fatal. The ancient Greeks referred to arrow poison as toxikon, short for toxikon pharmakon, literally, bow drug (from toxos, bow). As Latin toxicum, the word was applied more generally to any poison. The English word toxic comes from this Latin word.


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