ordinal

• Ordinal data, a statistical data type consisting of numerical scores that exist on an arbitrary numerical scale
• Ordinal date, a simple form of expressing a date using only the year and the day number within that year
• Ordinal indicator, the sign adjacent to a numeral denoting that it is an ordinal number
• Ordinal number in set theory, a number type with order structures
• Ordinal number (linguistics), a word representing the rank of a number
• Ordinal scale, ranking things that are not necessarily numbers
• Ordinal utility (economics): a utility function which is used only to describe the preference ordering between different outcomes.
• Regnal ordinal, used to distinguish monarchs and popes with the same regnal name
• In liturgy, an ordinal is a book that gives the ordo (ritual and rubrics) for celebrations
• In Anglicanism, the Ordinal is the book containing the rites for the ordination of deacons and priests, and the consecration of bishops. Typically, this is printed with the Book of Common Prayer.

• einen Aspekt der Zahlen, siehe Ordinalzahl
• ein Zahlwort der Reihenfolge, siehe Zahlwort
• hochgestellte Buchstaben, welche Ordinalzahlen kennzeichnen, siehe Ordinalzeichen
• eine grundlegende Klasse physikalischer und mathematischer Skalierung, siehe Ordinalskala

• al numeral (lingüística), el concepto de los números en el lenguaje humano;
• al número ordinal (numerales), el numeral usado para nombrar el elemento de una serie ordenada;
• al número ordinal (teoría de conjuntos), el concepto abstracto de ordinal en la teoría de conjuntos.

Os ordinais foram apresentados por Georg Cantor en 1883 para acomodar sequências infinitas e para classificar conjuntos com certos tipos de estruturas de ordem neles. Ele os derivou por acidente, enquanto trabalhava num problema que envolvia séries trigonométricas – veja em Georg Cantor.