Definitions for "Unstructured interview"
an ethnographic data-gathering technique usually used in the early stages of one's fieldwork in which interviewees are asked to respond to broad, open-ended questions.
The key feature of the unstructured interview is the free-ranging nature of the questions asked. The researcher does not have, nor needs to stick to any particular questions.
A research method involving an extended, open-ended interaction between an interviewer and an interviewee.