causative
adjective
caus·a·tive ˈkȯ-zə-tiv 
1
: effective or operating as a cause or agent
causative bacteria of cholera
2
: expressing causation
specifically : being a linguistic form that indicates that the subject causes an act to be performed or a condition to come into being
causative noun
causatively adverb
Example Sentences
A virus was found to be the causative agent of smallpox.
Recent Examples on the Web This headline and story imply a causative relationship between the Bolsonaro policy changes and the drop in homicides. 
WSJ, 5 July 2022 What’s happened is there’s now an assumption that these risk factors are causative rather than associative, says Elovitz. Katie Jennings, Forbes, 17 May 2022 On a scientific level, the specificity of genomic composition—for determining the Covid virus’s variation—was unimaginable for influenza in 1918, an era when doctors did not yet know the causative organism behind the pandemic. Howard Markel, Wired, 14 Jan. 2022 As such, there’s no exact proof of causative effect. Joshua Hawkins, BGR, 8 Dec. 2021 The county reported that deaths where fentanyl was a causative factor increased by 126 percent, from 69 to 156. Jim Vargas, San Diego Union-Tribune, 11 Aug. 2021 Blaming the deaths of 47 Black men on SCT as causative instead of associated is inaccurate and disrespectful. A. Kyle Mack, Scientific American, 20 June 2021 There are only two levels of data that can tell you whether something is causative. Lisa Drayer, CNN, 13 May 2021 But recently, blood clots and abnormal bleeding in a small number of vaccine recipients in European countries have cast doubt on its safety, although no causative link has been found between the patients’ conditions and the vaccine. New York Times, 16 Mar. 2021 See More
WSJ, 5 July 2022 What’s happened is there’s now an assumption that these risk factors are causative rather than associative, says Elovitz. Katie Jennings, Forbes, 17 May 2022 On a scientific level, the specificity of genomic composition—for determining the Covid virus’s variation—was unimaginable for influenza in 1918, an era when doctors did not yet know the causative organism behind the pandemic. Howard Markel, Wired, 14 Jan. 2022 As such, there’s no exact proof of causative effect. Joshua Hawkins, BGR, 8 Dec. 2021 The county reported that deaths where fentanyl was a causative factor increased by 126 percent, from 69 to 156. Jim Vargas, San Diego Union-Tribune, 11 Aug. 2021 Blaming the deaths of 47 Black men on SCT as causative instead of associated is inaccurate and disrespectful. A. Kyle Mack, Scientific American, 20 June 2021 There are only two levels of data that can tell you whether something is causative. Lisa Drayer, CNN, 13 May 2021 But recently, blood clots and abnormal bleeding in a small number of vaccine recipients in European countries have cast doubt on its safety, although no causative link has been found between the patients’ conditions and the vaccine. New York Times, 16 Mar. 2021 See More Word History
Etymology
Middle English causatyf (as noun; Old Scots causative as adjective), borrowed from Medieval Latin causātīvus, going back to Late Latin, "expressing reason, of a cause," from Latin causātus (past participle of causārī "to plead an action in law, plead as an excuse") + -īvus -ive — more at cause entry 2
First Known Use
15th century, in the meaning defined at sense 1
Legal Definition
causative
adjective
caus·a·tive ˈkȯ-zə-tiv
1
: effective or operating as a cause
the causative negligent act
2
: causal sense 2
the causative link between stress and coronary artery disease National Law Journal
National Law Journal