Nanoscience and nanotechnology (NST) focus on the creation and the exploration of materials' properties at the nanoscale. The estimations about the impact of the field on our daily life, the industrial demands for ensuring skilled workforce, and the need to form a nano-literate citizenry have triggered the incorporation of aspects of this cutting-edge field into school curricula on behalf of education researchers. Teachers play a vital role in the success of this endeavor. However, only a few studies up to date examine teachers' ideas of this field. In addition, there is not any analysis tool that would provide insights about how teachers' ideas are related to the key concepts and principles of NST. Concerning this gap, we describe in detail a deductive content analysis method, having been conducted to examine the meanings that 419 Greek primary school teachers give to NST. Results reveal the insufficient content knowledge of primary school teachers regarding NST.