Simple Definition of plenary
: attended by all the people who have the right to attend
: complete in every way
Examples of plenary in a sentence
A plenary meeting of the 500 members was held last summer.
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 of plenary
Middle English, from Late Latin plenarius, from Latin plenus full — more at full
First Known Use: 15th century
Synonym Discussion of plenary
Legal Definition of plenary
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