The definition of a trinomial is a math equation that has three terms which are connected by plus or minus notations.(noun)
An example of trinomial is 6x squared + 3x + 5.
Trinomial means the scientific name of a plant.(noun)
An example of a trinomial is a name which inclues the genus, species and the variety.
See trinomial in Webster's New World College Dictionary
Origin: tri- + (bi)nomial
See trinomial in American Heritage Dictionary 4
Origin: + (bi)nomial.
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