'twas /twoz, twəz/ (archaic or dialect) a contraction of it was

• wagon box
• wagon boxes
• wagoned
• wagoner
• wagoners
• wagonette
• wagonettes
• wagonful
• wagonfuls
• wagoning
• wagon-lit
• wagon-lits
• wagonload
• wagonloads
• wagon lock
• wagon locks
• wagon roof
• wagon roofs
• wagons
• wagons-lit
• wagon train
• wagon trains
• wagon vault
• wagonwright
• wagonwrights