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definitions

I-bar

[ahy-bahr]
noun
  1. an I-beam used for structural support, as in buildings or bridges.

Origin of I-bar

First recorded in 1885–90

I-beam

[ahy-beem]
noun
  1. a rolled or extruded metal beam having a cross section resembling an I.Compare H-beam.

Origin of I-beam

First recorded in 1890–95
Also called I-bar [ahy-bahr] /ˈaɪˌbɑr/.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for i-bar

I-beam

noun
  1. a rolled steel joist or a girder with a cross section in the form of a capital letter ICompare H-beam
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