semidetached Syllabification: (sem·i·de·tached)Pronunciation: /ˌsemēdiˈtaCHt, ˌsemˌī-/Translate semidetached | into Spanish Definition of semidetached adjective (of a house) joined to another house on one side only by a common wall. noun British a semidetached house. semidetached in other Oxford dictionaries