"In the American experience we assume that a house has windows on all four sides and sideyards to separate our house from that of our neighbor. it wasn't until I lived in England and discovered that this most common type of housing in our country was referred to as 'detached' housing in that country to differentiate it from the 'attached' housing in which they commonly live. In England the dream of a young couple is to attain a 'semi' i.e., a semidetached house, or what we call a duplex, while we in this richer country aspire to attain a detached house."
Smolski, Chester, "A Scheme for Using our Valuable Land Wisely" (2000). Smolski Texts. 276.