In the last decades, science literacy has been progressively emphasised as an aim of science education. However, the science education literature does not present a consensus about both the meaning of science literacy. By studying such literature, we identified some of these aspects that may also be relevant for promoting students' critical education. These are decision-making, critical thinking, critical positioning, and self-awareness-raising. Based on this review of the literature, our main goal has been that of discussing how these aspects could be inter-related and favour science literacy in the context of nature of science teaching. This does not mean coming up with a new ready definition for science literacy, but rather enhancing the discussion and supporting its understanding as something more complex, resulting from an intricate interaction of many components and that may be constantly promoted and developed in science lessons. Such a perspective can help teachers' perceptions that science literacy of their students is an attainable aim, as well as encourage them to foster it.