I beam
Noun
Meaning
girder having a cross section resembling the letter `I'
Source: WordNetAlternative names
I-beam
Synonyms
Hypernyms
Examples
The obvious convenience of functions of this kind, which appeared to be part of the language, led to the introduction of the monadic I-beam function for direct use by anyone.
The I-beam functions were first introduced by the system programmers to allow them to execute System/360 instructions from within APL programs, and thus use APL as a direct aid in their programming activity.