girthweld UK /ˈɡɜːθˌwɛld/US /ˈɡɜɹθˌwɛld/ noun1 •A circumferential weld that joins two cylindrical sections, such as pipes or pressure vessels, by welding around their perimeter. Girth welds are commonly used in pipeline construction.Thus, experimental work is needed to verify which model most accurately predicts girthweld behavior. — 1980 formsgirthwelds