grou - high
- hard plaster
- hard points
- hard porcelain
- hard putty
- hard radiation
- hard rendezvous
- hard rock
- hard rock deposit
- hard rock drill
- hard rubber
- hard rubber scrap
- hard sand
- hard sectoring
- hard shoulder
- hard solder
- hard spot
- hard spring
- hard steering
- hard stoping
- hard superconductor
- hard surface aerodrome
- hard surface cleaning composition
- hard surfacing
- hard swell
- hard tap
- hard taphole
- hard temper
- hard top
- hard waste
- hard water
- hard wax
- hard wind
- hard wiring
- hard X-ray machine
- hard zinc
- hard [harsh] image
- hard [high] vacuum
- hard [moderate] gale
- hard-alloy crown bit
- hard-alloy drill bit