What does trinomial mean?
A trinomial is an expression or name made up of three parts. In algebra, it is a polynomial containing three terms, as in a trinomial equation or expansion; in statistics, the term also appears in the name of a trinomial distribution, which models the frequencies of three possible outcomes. Biological taxonomy uses a trinomial for a three-part scientific name, generally including a genus, species, and subspecies. As an adjective, trinomial means involving three terms or components. The word belongs to specialized mathematical and scientific vocabulary rather than ordinary conversation, but it is useful because it identifies a precise three-part structure. It also contrasts usefully with monomial, binomial, and the more general polynomial. The term reflects its Greek and Latin roots: the prefix tri- means “three,” while the second element comes from a word associated with naming, law, or arrangement. Overall, trinomial gives concise precision to any expression, distribution, or classification organized around exactly three elements.
A mathematical expression or equation consisting of three terms. In biological taxonomy, a trinomial is a scientific name formed from three parts, typically a genus, species, and subspecies.
"Each trinomial in the expansion represents a different combination of the available terms."
The algebraic sense is standard in mathematics, while the taxonomic sense is used in biological classification.
Consisting of or involving three terms, names, or parts.
"The catalogue records the trinomial designation of each subspecies."
This is primarily a formal technical adjective used in mathematics, statistics, and biological taxonomy.
The plural is used for three-term mathematical expressions or three-part taxonomic names considered individually.
"The chapter compares several trinomials with the same degree but different coefficients."
Three parts, three terms, three-name precision: trinomial is the specialist word for anything built from a trio.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does trinomial come from?
The English word dates from the seventeenth century and was formed from Latin trinomium, meaning a three-term expression or name. Its elements ultimately relate to Greek tri-, meaning “three,” and a root associated with naming, law, or arrangement, reflected in related mathematical terms such as binomial and monomial. The same root was later extended to polynomial, which refers generally to expressions with a greater number of terms.
Related word forms
How trinomial is actually used
Trinomial is formal and technical, used mainly in mathematics, statistics, and biological taxonomy. In taxonomy, the three-part form is especially associated with the designation of a subspecies. British and American users generally spell it identically; pronunciation differs chiefly in the treatment of the second vowel.
Easily confused with trinomial
A binomial has two terms or parts, whereas a trinomial has three.
Ternomial is a rare synonym for a three-term expression; trinomial is the standard and much more common term.