- hypoMelancholy; a fit of hypochondria; a morbid depression.
- hyporheicBeneath or alongside the bed of a stream, where water percolates through interstices between the rocks leading to mixing of groundwater and surface water
- hypocaustAn underfloor space or flue through which heat from a furnace passes to heat the floor of a room or a bath.
- hyponymA more specific term; a subordinate grouping word or phrase; a term designating a subclass of another more general class described by the given word.
- hypostheniaweakness; subnormal strength