Filioque is a Latin term meaning and the Son. The inclusion or omission of this term in the Niceno-Constantinopolitan Creed has been a theological and procedural controversy, a major cause of the schism of 1054 AD between the Western and Eastern churches, and an ongoing source of disagreement for over a thousand years. The clause is inserted in the words Qui ex Patre [Filioque] procedit, 'Who proceeds from the Father [and the Son]', which specifically address the procession of the Holy Spirit, defining whether He proceeds from the Father, or from the Father and the Son.