1. Sometimes generalized as “fake news”, disinformation is “false information that is deliberately created or disseminated with the express purpose to cause harm”. Disinformation is deliberately false, which distinguishes it from malinformation which is true information that is disseminated to cause harm. It is also distinct from misinformation, which is false information disseminated by accident. An example of disinformation is twitter ads claiming you could vote by text near to the 2016 election.
Source: Election Cybersecurity 101 Field Guide – Glossary Center for Democracy & Technology https://cdt.org/insight/election-cybersecurity-101-field-guide-glossary/
2. Carefully contrived misinformation prepared by an intelligence or CI [Counterintelligence] service for the purpose of misleading, deluding, disrupting, or undermining confidence in individuals, organizations, or governments. (CI Community Lexicon).
Source: Terms & Definitions of Interest for DoD Counterintelligence Professionals, Office of the National Counterintelligence, https://www.dni.gov/files/NCSC/documents/ci/CI_Glossary.pdf
3. False information deliberately spread to deceive.
Source: U.S. Cyberspace Solarium Commission, March 2020, https://subscriber.politicopro.com/f/?id=00000170-c638-d8f7-a7f1-f63b33510000