A joggle is a joint or projection that interlocks blocks (such as a lintel's stone blocks or an arch's voussoirs). Often joggles are semicircular and knob-shaped, so joggled stones have a jigsaw- or zigzag-like pattern. Joggling can be found in pre-Frankish buildings, in Roman Spain and Roman France. In Islamic architecture, the earliest joggles were in the desert castles of the Umayyad Caliphate, such as Qasr al-Hayr al-Sharqi. In Mamluk architecture, joggling is usually combined with ablaq (alternating colors). Joggling also characterize Ottoman architecture in Cairo. The protruding joggle is also called a "he-joggle", whereas the corresponding slot is called a "she-joggle".
See also Dovetail joint: dovetailing can be considered a type of joggling.
References


![Joggle (architecture): Mausoleum of Theodoric, Ravenna: joggles[1] resembling rabbets (rebates)](https://upload.wikimedia.org/wikipedia/commons/thumb/6/60/Voussoirs%2C_Mausoleum_of_Theodoric%2C_Ravenna%2C_2012_%28cropped%29.jpg/500px-Voussoirs%2C_Mausoleum_of_Theodoric%2C_Ravenna%2C_2012_%28cropped%29.jpg?utm_source=en.wikipedia.org&utm_campaign=parser&utm_content=thumbnail)
