Since the early 2000s, a proliferation of new words and neologisms has appeared in the literature intending to characterize new ways of building the city: guerilla gardening, Park(Ing) day, DIY, tactical urbanisms... This paper argues that this new lexicon illustrates power play evolutions in the urban planning of contemporary cities, especially in the Western world. In our opinion, this plurality of terms indicates the assertion of urban dwellers as a creative force capable of materially transforming public spaces. Common points and differences between those new words are analyzed, thanks in part to a typology of urban dwellers initiatives. Their capacity to invert the traditional decision making process in urban planning is finally examined, from a top-down to a bottom-up perspective.