quadri-, quadra-, quad-, quadru-

Conveying four rows or ranks: There are plants that have quadrifarious leaves.

A system that has four details, compartments, or pieces: The professors and deans at the local university were intrigued by the quadrifurcation of the student government which emerged after the students met with the visiting politician, because they wanted a carefully balanced form of government with each of the four branches providing oversight of each other.

Someone who has married four times and as a result, has four spouses; such as, four wives or four husbands at the same time.

Married to four spouses at the same time or a fourth marriage.

Using, written in, etc., four languages.

All of these are variations in form of quadraphonic, et al.