adjective ple·na·ry \ˈplē-nə-rē, ˈple-\

Definition of plenary

  1. 1 :  complete in every respect :  absolute, unqualified plenary power

  2. 2 :  fully attended or constituted by all entitled to be present a plenary session

plenary was our Word of the Day on 05/21/2009. Hear the podcast!

Examples of plenary in a sentence

  1. A plenary meeting of the 500 members was held last summer.

  2. plenary sessions of the legislature

Did You Know?

In the 14th century, the monk Robert of Brunne described a situation in which all the knights of King Arthur's Round Table were present at court by writing, "When Arthures court was plener, and alle were comen, fer and ner. . . ." For 200 years, "plener" (also spelled "plenar") served English well for both senses that we reserve for "plenary" today. But we'd borrowed "plener" from Anglo-French, and, although the French had relied on Latin plenus ("full") for their word, the revival of interest in the Classics during the English Renaissance led scholars to prefer purer Latin origins. In the 15th century, English speakers turned to Late Latin plenarius and came up with "plenary." ("Plenarius" also comes from "plenus," which is the source of our "plenty" and "replenish" as well.)

Origin and Etymology of plenary

Middle English, from Late Latin plenarius, from Latin plenus full — more at full

First Known Use: 15th century

Synonym Discussion of plenary

full, complete, plenary, replete mean containing all that is wanted or needed or possible. full implies the presence or inclusion of everything that is wanted or required by something or that can be held, contained, or attained by it. a full schedule complete applies when all that is needed is present. a complete picture of the situation plenary adds to complete the implication of fullness without qualification. given plenary power replete implies being filled to the brim or to satiety. replete with delightful details

PLENARY Defined for English Language Learners


adjective ple·na·ry \ˈplē-nə-rē, ˈple-\

Definition of plenary for English Language Learners

  • : attended by all the people who have the right to attend

  • : complete in every way

Law Dictionary


adjective ple·na·ry \ˈplē-nə-rē, ˈple-\

Legal Definition of plenary

  1. :  full and complete in every respect: as a :  absolute 1 plenary power b :  fully attended or constituted a plenary session of the legislature c :  including all steps in due order a plenary proceeding — compare summary

Seen and Heard

What made you want to look up plenary? Please tell us where you read or heard it (including the quote, if possible).


to help become familiar with something

Get Word of the Day daily email!


Take a 3-minute break and test your skills!

  • ludwig-richter-spring-has-arrived
  • Which is a synonym of upbraid?
Name That Thing

Test your visual vocabulary with our 10-question challenge!


Test Your Knowledge - and learn some interesting things along the way.