What does toxic mean?
Toxic is an adjective meaning poisonous or capable of causing poisoning. It also describes substances, conditions, or behaviours that are profoundly harmful or damaging, such as toxic waste, a toxic workplace, or a toxic relationship. In contemporary usage, the figurative sense is often the more familiar one: calling something “toxic” suggests that it causes continuing harm rather than merely a brief inconvenience. The word can refer to physical danger, emotional or psychological damage, persistent social conflict, or an unpleasant atmosphere. Because it is strongly negative, it is often used where a serious problem needs to be identified, although speakers may also use it informally to exaggerate minor annoyances. The noun “toxic,” meaning a poisonous substance, exists but is much less common than the adjective.
Containing poison or capable of causing poisoning; figuratively, extremely harmful, damaging, or persistently unpleasant.
"The report warned that the chemicals could produce toxic fumes."
The figurative use is highly common and can describe relationships, environments, organisations, and patterns of behaviour.
A poisonous substance or toxin.
"The scientists tested the substance to determine whether it was a toxic."
This noun is uncommon and chiefly informal; the adjective is the word's dominant form.
The plural is rare because the noun is itself uncommon; singular “a toxic” is more typical in informal use.
"The samples were screened for known toxics."
Toxic and toxin share a Greek root meaning “poison”: the word that describes danger also names the poison responsible.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of toxic
Toxic comes through Latin toxicus from Greek toxikos, meaning “poisonous,” which was derived from toxikon, “poison.” The related English words toxin, toxicity, and toxicology developed from the same classical root. Its earliest sense referred specifically to poison or poisoning before the adjective acquired its broader figurative meanings.
Related word forms
How toxic is actually used
The figurative sense is very common in both formal and informal English, especially for relationships, workplaces, behaviours, and environments. It can range from a serious moral judgment to informal exaggeration, so context helps determine the degree of condemnation intended. The noun is uncommon compared with the adjective.
Easily confused with toxic
Toxic is normally an adjective describing something poisonous or harmful, whereas a toxin is a poisonous substance itself.