Semi-structured interviews are a data collection method for qualitative research, in which interviewees are asked questions about overarching themes rather than a from a script of questions, which allows participants to present responses relevant to the themes in question and potentially present unexpected themes as well.
Citation: Lewis-Beck, M., Bryman, A., & Liao, T. (2004). The SAGE encyclopedia of social science research methods (Vols. 1–3). Thousand Oaks, CA: SAGE Publications. https://doi.org/10.4135/9781412950589