From Longman Dictionary of Contemporary Englishgirdergir‧der /ˈɡɜːdə $ ˈɡɜːrdər/ noun [countable] TBCa strong beam, made of iron or steel, that supports a floor, roof, or bridge
Examples from the Corpus
girder• A girder is a beam that supports other beams or is made up of separate beams joined together.• As the train approaches a junction, a second bottom girder supports the train on both sides.• Chord sequences register like rivets hammered into girders.• They crowded whatever elevators still worked or wearily scaled buckled stairways or girders.• They would strengthen the bridge without making major changes in the steel girder system above that might look out of place.• Daak had stopped half-way up the girder and, holding on with one hand, was flailing the air with his chainsword.• It went on a line into the stands and hit the same upright girder.Origin girder (1600-1700) gird 