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baseboard

American  
[beys-bawrd, -bohrd] / ˈbeɪsˌbɔrd, -ˌboʊrd /

noun

  1. Also called mopboard, skirt.  a board forming the foot of an interior wall.

  2. a board forming the base bases of anything.

baseboard British  
/ ˈbeɪsˌbɔːd /

noun

  1. a board functioning as the base of anything

  2. Also called: skirting board.  a skirting made of wood

"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 baseboard

An Americanism dating back to 1850–55; base 1 + board

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.