Helm·holtz 
(hĕlmhōlts′), Hermann Ludwig Ferdinand von 1821-1894.
(hĕlmhōlts′), Hermann Ludwig Ferdinand von 1821-1894. German physicist and physiologist who formulated the law of the conservation of energy (1847) and invented an ophthalmoscope (1851).
- heaviness
- Heaviside layer
- heavy
- heavy chain
- heavy-duty
- heavy-footed
- heavy-handed
- heavy-handedness
- heavy-hearted
- heavy-heartedly
- heavy-heartedness
- heavy hitter
- heavy hydrogen
- heavy ion
- heavy-laden
- heavy lifting
- heavy metal
- heavyset
- heavy spar
- heavy water
- heavyweight
- Heb.
- hebdomad
- hebdomadal
- hebdomadally