The ancient Greek word oikos (ancient Greek: , plural: ; English prefix: eco- for ecology and economics) refers to three related but distinct concepts: the family, the family's property, and the house. Its meaning shifts even within texts. The oikos was the basic unit of society in most Greek city-states. In normal Attic usage the oikos, in the context of families, referred to a line of descent from father to son from generation to generation. Alternatively, as Aristotle used it in his Politics, the term was sometimes used to refer to everybody living in a given house. Thus, the head of the oikos, along with his immediate family and his slaves, would all be encompassed. Large oikoi also had farms that were usually tended by the slaves, which were also the basic agricultural unit of the ancient Greek economy. Layout Traditional interpretations of the layout of the oikos in Classical Athens have divided into men's and women's spaces, with an area known as the gynaikon or gynaikonitis associated with women's activities such as cooking and textiles work, and an area restricted to men called the andron. In Lysias' speech On the Murder of Eratosthenes, the women's rooms were said to be situated above the men's quarters, while in Xenophon the women's and men's quarters are next to one another. More recent scholarship from historians such as Lisa Nevett and Lin Foxhall has argued for a more flexible approach to household space, with rooms not simply having a single fixed function, and gendering of space not being as simple as some rooms being for men and others for women. It has been argued that instead of dividing the household space into "male" and "female" areas, it is more accurate to look at areas as being private or public. In this model, access to the private areas were restricted to the family, while public areas accommodated visitors. In Olynthos and Halieis, street plans in the classical city were rectilinear, and thus houses were of regular shapes and sizes. By contrast, in Athens houses appear to have varied much more in size and shape. In the classical period, houses excavated from Olynthos were "invariably" organised around a colonnaded courtyard. Likewise, of the houses excavated at Halieis in the Argolid, most of the houses seem to have had a single entrance which gave access to a court, and Nevett also cites three buildings excavated