This list of informally named dinosaurs is a listing of dinosaurs (excluding Aves; birds and their extinct relatives) that have never been given formally published scientific names. This list only includes names that were not properly published ("unavailable names") and have not since been published under a valid name (see list of dinosaur genera for valid names). The following types of names are present on this list:
- Nomen nudum, Latin for "naked name": A name that has appeared in print but has not yet been formally published by the standards of the International Commission on Zoological Nomenclature. Nomina nuda (the plural form) are invalid, and are therefore not italicized as a proper generic name would be.
- Nomen manuscriptum, Latin for "manuscript name": A name that appears in manuscript but was not formally published. A nomen manuscriptum is equivalent to a nomen nudum for everything except the method of publication, and description.
- Nomen ex dissertationae, Latin for "dissertation name": A name that appears in a dissertation but was not formally published.
- Nicknames or descriptive names given to specimens or taxa by researchers or the press.