The invention relates to a tab (5) for a sealing gasket device of a part of an aircraft gas turbine engine. The tab is arranged in respective slots of adjacent sectorized parts of the turbine engine nozzle. This tab has two bulging ends (51a, 51b) joined by a thinner intermediate part (51c) each having a connection with the other (53a, 53b), which can deform into a flat position by bracing the tab, when excess pressure is applied to its intermediate part from one side of the tab.