There are a number of early documents listing Toxteth and Smithdown as being together, which culminate in the interesting description of rents in the time of Charles I for ‘Toxteth, Smithdon Moss and Letherpoole’.
The Domesday listings give Smithdown ( or Esmedun) as a huge area ( Picton determines the equivalence of 180 statute acres), and given the nearby forests of West Derby to the East ( at Wavertree), Toxteth to the South and SouthWest, and the fact it has a very small tax (geld unit), it would be reasonable to assume a lot of the land is unworkable, so probably either fen or forest.
Over time the place referred to later as Toxteth Park seems to have overlapped in written descriptions. In Domesday there are two Toxteth entries ( as the original name Stochestede), which Picton determines to etymologically mean ‘the wooden settlement’, suggesting two land holdings within the forest. Over time the names seem to have conflated, and by the time of the formation of Liverpool King John is creating the Royal Toxteth Park from the landholdings, swapped for ground in Litherland.
Don't worry, we're nearly up to Liverpool history proper, with talk about the actual plot we're on about and the building of the Square and everything!