What is "cleche"

In heraldry, a cross (or other ordinary) cleché, or clechée, flares out at the tips in a shape resembling the handle of an old-fashioned key ( French clé). The outstanding example is the Occitan cross, in the coat of arms of the counts of Toulouse: Gules, a cross cléchée, pommetty and voided Or. Because this cross is also voided (hollow), some writers have taken the term cléché either to be a synonym of voided or to include voiding as a defining feature.