| barb(noun, beam, tunnel, rod, duct) |
| axis(noun, beam, tunnel, rod, duct) |
| axle(noun, beam, tunnel, rod, duct) |
| column(noun, beam, tunnel, rod, duct) |
| conduit(noun, beam, tunnel, rod, duct) |
| diaphysis(noun, beam, tunnel, rod, duct) |
| flue(noun, beam, tunnel, rod, duct) |
| helve(noun, beam, tunnel, rod, duct) |
| hole(noun, beam, tunnel, rod, duct) |
| monolith(noun, beam, tunnel, rod, duct) |
| obelisk(noun, beam, tunnel, rod, duct) |
| pilaster |
| pillar(noun, beam, tunnel, rod, duct) |
| pinnacle(noun, beam, tunnel, rod, duct) |
| shaft(noun, something, tunnel, duct, chimney) |
| spindle(noun, beam, tunnel, rod, duct) |
| spire(noun, beam, tunnel, rod, duct) |
| tongue(noun, beam, tunnel, rod, duct) |
| vent(noun, beam, tunnel, rod, duct) |
| abutment |