threeitem

Threeitem is a term used informally to describe a unit or structure that consists of three related items. It is not a formally defined term in major knowledge bases, but it appears in various technical and design contexts to convey a simple, three-part composition.

In computing and data modeling, threeitem commonly refers to a three-tuple or triple: an ordered collection of three elements. Depending on the context, the three items may be homogeneous or heterogeneous. In databases and knowledge representation, a threeitem can describe a row with three fields, or a subject–predicate–object triple in RDF.

In packaging, commerce, and product design, a threeitem bundle describes a package that groups three products together for sale or display. In user interfaces and APIs, a threeitem structure may be used to return or process three related values, such as coordinates (x, y, z) or dimensions (width, height, depth).

Terminology around threeitem is not standardized; practitioners usually specify the exact semantics—order, cardinality, and allowed types—when using the term. Without explicit definition the meaning can be ambiguous across disciplines.

Related concepts include tuple, triple, and RDF triple, which describe similar three-element structures in mathematics and information science.