TOXIC
toxic
(adjective) of or relating to or caused by a toxin or poison; “suffering from exposure to toxic substances”
Source: WordNet® 3.1
Etymology
Adjective
toxic (comparative more toxic, superlative most toxic)
(toxicology, pharmaceutical drug) Having a chemical nature that is harmful to health or lethal if consumed or otherwise entering into the body in sufficient quantities.
Synonyms: poisonous, venomous
(medicine) Appearing grossly unwell; characterised by serious, potentially life-threatening compromise in the respiratory, circulatory or other body systems.
(figurative) Severely negative or harmful.
(figurative, of a person) Hateful or strongly antipathetic.
Source: Wiktionary
Tox"ic, Tox"ic*al, a. Etym: [L. toxicum poison, originally, a poison
in which arrows were dipped, Gr. Intoxicate.]
Definition: Of or pertaining to poison; poisonous; as, toxic medicines.
Source: Webster’s Unabridged Dictionary 1913 Edition