nésimo

Nésimo is a Portuguese ordinal used to indicate the position of an element within a sequence. It functions as an adjective that modifies nouns such as termo, elemento, or item in mathematical, computer science, or general prose contexts. The standard spelling is enésimo, and in technical writing the compound form n-ésimo is commonly used to signal an arbitrary index n, as in o n-ésimo termo da sequência.

Spelling and variants: Enésimo is the normative form in most dictionaries. The hyphenated form n-ésimo is frequent in formulas and algorithms to emphasize the index n. The isolated form né simo is not considered standard in formal Portuguese and may appear as a typographical variant or error in informal texts.

Etymology: The term derives from the suffix -ésimo, which marks ordinal numerals in Portuguese. The prefix n- represents a variable natural number, yielding the expression “n-ésimo” for “the nth.” The root concept is shared with related forms such as enésimo, both conveying the idea of a particular position in a sequence.

Usage: It is widely used in mathematics, statistics, and computer science, as well as in everyday language to refer to an unspecified term or element in a series. Examples include “o enésimo termo da sequência a_n” and “o n-ésimo elemento da lista.” The phrase can appear in idiomatic expressions like “no enésimo caso.”

See also: Ordinal numbers in Portuguese; Notation in mathematics; Sequence terminology.