gantries

noun pl. gantries

1. a frame on which barrels can be set horizontally
2. a framework that spans a distance, often moving on wheels at each end, used for carrying a traveling crane
3. a bridgelike framework over railroad tracks, for supporting signals or for loading
4. ☆ a wheeled framework with a crane, platforms at different levels, etc., used for assembling, positioning, and servicing a large rocket at its launching site