follow Dictionary.com

What is the X in X-mas?

keystone joist

noun
1.
a reinforced-concrete joist with sloping sides and the top wider than the bottom.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source

Word of the Day

Difficulty index for keystone joist

Few English speakers likely know this word

Word Value for key

10
9
Scrabble Words With Friends