China 
Africa 
- Headwaters
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- Health Insurance Portability and Accountability Act
- Health and social care
- Health data
- Health indicators
- Health informatics
- Health information management
- Health physics
- Health systems engineering
- Health technology
- HealthMap
- Healthcare analytics
- Healthy building
- Heap
- Heap leaching
- Heaps' law
- Heapsort
- Hearing aids
- Hearing conservation program
- Hearing loss
- Hearing protection
- Hearing protection devices
- Hearing range
- Hearing test
- Heart
- Heart attack
- Heart block
- Heart disease
- Heart failure
- Heart failure with preserved ejection fraction
- Heart murmurs
- Heart rate
- Heart rate monitor
- Heart rate turbulence
- Heart sounds
- Heart transplant
- Heart valve
- Heartbeat
- Heartbleed
- Heartburn
- Hearth
- Heat
- Heat bath
- Heat capacity
- Heat capacity ratio
- Heat cramps
- Heat death of the universe
- Heat detector
- Heat dissipation
- Heat engine
- Heat equation
- Heat exchanger
- Heat exhaustion
- Heat flux
- Heat flux sensor
- Heat illness
- Heat kernel
- Heat lamps
- Heat maps
- Heat of combustion
- Heat of fusion
- Heat of solution
- Heat of vaporization
- Heat pipes
- Heat press
- Heat pumps
- Heat rate
- Heat setting
- Heat shields
- Heat shock proteins
- Heat sinks
- Heat spreader
- Heat stroke
- Heat syncope
- Heat therapy
- Heat transfer
- Heat transfer coefficient
- Heat transfer enhancement
- Heat transfer fluid
- Heat traps
- Heat treating
- Heat treatment
- Heat-transfer fluid
- Heated glass
- Heater
- Heater core
- Heating degree day
- Heating elements
- Heating mantle
- Heating oil
- Heating plants
- Heating system
- Heatsetting
- Heaviside step function
- Heavy chain
- Heavy crude oil
- Heavy equipment
- Heavy equipment operator
- Heavy fermion
- Heavy fuel oil
- Heavy ion
- Heavy liquid
- Heavy metals
- Heavy mineral analysis
- Heavy minerals
- Heavy traffic approximation
- Heavy water
- Heavy water reactor
- Heavy-chain antibody
- Heavy-tailed distribution
- Heazlewoodite
- Hebbian learning
- Heck reaction
- Hectare
- Hectorite
- Hedenbergite
- Hedonic regression
- Heel
- Heel effect
- Height above ground level
- Height above mean sea level
- Height function
- Height gauge
- Heijunka
- Heisenberg group
- Heisenberg picture
- Hele-Shaw flow
- Helical
- Helical antennas
- Helicase-dependent amplification
- Helicene
- Helicity
- Helicobacter pylori
- Helicoid
- Helicon
- Helicopter dynamics
- Helicopter rotor
- Helicopters
- Helicotrema
- Heliostats
- Heliox
- Helium
- Helium analyzer
- Helium atom
- Helium dilution
- Helium dimer
- Helium-3