Consisting of or relating to two names or terms.
1. Mathematics A polynomial with two terms.
2. Biology A taxonomic name in binomial nomenclature.
[From New Latin binōmius, having two names : BI-1 + French nom, name (from Latin nōmen; see NOMINAL).]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.