Justin E. H. Smith in his own blog:
‘Nature’, in common usage, can mean a number of different things. Sometimes it refers to the external world, and more particularly to the earth’s surface, and more particularly still to that part of the earth’s surface made up of biomass. In the same general conceptual vicinity, we also find the notion of nature as environment, as the surrounding medium through which we move. At other times, ‘nature’ refers to the particular nature of a given being, or what is sometimes called ‘essence’– what it is to be a particular entity rather than another.
The first sense of ‘nature’ reflects the word’s etymology, which is rooted in the Latin verbnasci, ‘to be born’. Nature, on this understanding, is that which undergoes generation and growth (and generally also corruption or death). This connection between nature and birth is similarly reflected in the Slavic and many other Indo-European languages (in Russian, for example, nature is priroda, connected to the verb rodit’sia, ‘to be born’; in the Sanskrit prakṛtiby contrast the verbal root has to do more with active creation than with generation). If less evidently, the concepts of generation and growth are also embedded in the Greek term physis, from which of course we get both ‘physical’ and what is sometimes held to lie beyond this, the ‘metaphysical’.