grou - high
- helical welded tube
- helical wire-spaced core subassembly
- helical [helix] antenna
- helical [helix] waveguide
- helical(-recording) tape
- helical(-recording) tape
- helical(-scan) video tape recorder
- helical(-scan) video tape recorder
- helical-coil heat exchanger
- helical-flute (milling )cutter
- helical-flute (milling )cutter
- helical-track resistor
- helical-welded pipe
- helically fluted reamer
- helicline
- helicoid
- helicoid conveyor
- helicon
- helicone
- helicopter
- helicopter (landing )deck
- helicopter (landing )deck
- helicopter (landing )platform
- helicopter (landing )platform
- helicopter electromagnetics
- helicopter lift
- helicopter logging operation
- helicopter survey
- helicopter yarding
- helicopter-type landing
- helideck
- heliocentric transfer altitude
- heliogeophysical forecast
- heliogram
- heliograph
- heliographic print
- heliographic [helioprinting] paper
- heliography
- heliogravure
- helion