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variant of pleo-.
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Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022


What does plio- mean?

Plio– is a combining form used like a prefix meaning “more.” It is very occasionally used in scientific terms, especially in biology.

Plio– comes from Greek pleíōn, meaning “more.” The Latin cognate of pleíōn is plūs “more,” which is the source of terms such as plural and plus. To learn more, check out our entries for these two words.

What are variants of plio-?

Plio– is a very rare variant of pleo. Another rare variation of pleo– is pleio. Want to know more? Read our Words That Use articles about pleo– and pleio-.

Examples of plio-

A scientific term you may have come across that features the form plio– is Pliocene, or Pleiocene, “an epoch occurring from 10 to 2 million years ago, characterized by increased size and numbers of mammals, by the growth of mountains, and by global climatic cooling.”

The plio– part of the word means “more.” The cene part of the word is a combining form that means “new” or “recent,” from Greek kainós. Pliocene literally translates to “more recent.”

What are some words that use the combining form plio-?

What are some other forms that plio– may be commonly confused with?

Not every word that begins with the exact letters plio-, such as Pliohippus or Pliofilm, is necessarily using the combining form plio– to denote “more.” Learn why Pliofilm is the name of a kind of rubber at our entry for the word.

Break it down!

The combining form saurus is used to name extinct reptiles, as in dinosaurs. With this in mind, what does Pliosaurus literally mean?

British Dictionary definitions for plio-


pleo- or pleio-

combining form
greater in size, extent, degree, etc; morePliocene

Word Origin for plio-

from Greek pleiōn more, from polus much, many
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012