Abstract: A toy building element comprising primary coupling means that extend from a top wall and comprise a cavity that contains secondary coupling means that are configured for being able to cooperate frictionally with the primary coupling means on a neighbouring element in a number of friction areas. According to the invention there are also primary locking means that are situated at the end of notches in the primary coupling means, wherein the locking means are configured for snap-lockingly engaging with secondary locking means in the cavity of a neighbouring element in same locking areas that are situated outside said friction areas, in which the secondary locking means are elastically resilient in directions in parallel with the top wall of the building element and are substantially elastically relieved in an interconnected position.