Emerging technologies can have profound conceptual implications. Their emergence frequently calls for the articulation of new concepts, or for modifications and novel applications of concepts that are already entrenched in communication and thought. In this paper, we introduce the notion of “conceptual appropriation” to capture the dynamics between concepts and emerging technologies. By conceptual appropriation, we mean the novel application of a value-laden concept to lay a contestable claim on an underdetermined phenomenon. We illustrate the dynamics of conceptual appropriation by (...) analyzing the concept NATURE and its uptake in three discourses of emerging technology: cellular agriculture, solar geo-engineering, and biomimicry. We argue that NATURE and its cognate NATURALNESS are strongly valanced concepts upon which different stakeholders lay a claim. In doing so, stakeholders advance distinct conceptions of nature, typically to suit their own interests. Our case-studies illustrate how in discourses on emerging technology, the application of value-concepts is entangled with ideological stakes and power dynamics. (shrink)