tierced
/tɪəst
/(also tiercé /ˈtjəːseɪ/)
adjective Heraldry
Divided into three equal parts of different tinctures.They are an example of the rare form of tierced arms, that is three coats of arms set side by side.
Origin
Early 18th century: originally as tiercé 'divided into three parts', French past participle of tiercer.