To save this word, you'll need to log in.
Definition of I beam
: an iron or steel beam that is I-shaped in cross section
Keep scrolling for more
Comments on I beam
What made you want to look up I beam? Please tell us where you read or heard it (including the quote, if possible).
Test Your Vocabulary
Intact Latin Quiz
- What did focus mean in Latin?
Can you spell these 10 commonly misspelled words?
TAKE THE QUIZ
Test Your Knowledge - and learn some interesting things along the way.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridgedWords at Play
Ask the Editors
Word Games
- Intact Latin Quiz
What did each of these words mean to ancient Romans?
Take the quiz - The Eponym Quiz
Do you know these words that come from names?
Take the quiz - Spell It
Can you spell these 10 commonly misspelled words?
Take the quiz - Add Diction
Build a chain of words by adding one letter at a time.
Play the game
Share I beam
Time Traveler for I beam
The first known use of I beam was circa 1889
See more words from the same year