From Science Europe Data Glossary
Definition: research data is any (digital or analogous) object or evidence that is needed to underpin research.
Explanation: research data refers to information, in particular facts or numbers, collected to be examined and considered as a basis for reasoning, discussion, or calculation. Examples of research data include statistics, results of experiments, measurements, observations resulting from fieldwork, survey results, interview recordings, artefacts and images.
Alternative definition: research data also means data in the form of facts, observations, images, computer program results, recordings, measurements or experiences on which an argument, theory, test or hypothesis, or another research output is based.
Explanation: research data includes: laboratory notebooks; field notebooks; primary research data (including research data in hardcopy or in computer readable form); questionnaires; audiotapes; videotapes; models; photographs; films; test responses. Research collections may include slides; artefacts; specimens; samples. Provenance information about the data might also be included: the how, when and where it was collected, and with what means (for example, with which instrument or measuring device). The software code used to generate, annotate or analyse the data may also be included. Other sources confirm that there is no single definition for the term "research data". The definition can vary by discipline or by regulatory agency. Generally, however, the term refers to data in any format or medium that relate to or support research, scholarship, or artistic activity.
References: http://ands.org.au/guides/what-is-research-data.html; http://cflegacy.research.umn.edu/datamgtq2/data_p.html