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interrex

American  
[in-ter-reks] / ˈɪn tərˌrɛks /

noun

plural

interreges

  1. a person holding supreme authority in a state during an interregnum.

interrex British  
/ ˌɪntəˈrɛks /

noun

  1. a person who governs during an interregnum; provisional ruler

"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

Etymology

Origin of interrex

From Latin, dating back to 1570–80; inter-, rex

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.