mine·shaft 
(mīnshăft′)
(mīnshăft′)n.
A vertical or sloping passageway made in the earth for finding or mining ore and ventilating underground excavations.
- hydrotherapy
- hydrothermal
- hydrothermally
- hydrothermal vent
- hydrothorax
- hydrotropic
- hydrotropism
- hydrous
- hydroxide
- hydroxide ion
- hydroxy
- hydroxyapatite
- hydroxybutyric acid
- hydroxychloroquine
- hydroxyl
- hydroxylamine
- hydroxylate
- hydroxylation
- hydroxylic
- hydroxyl ion
- hydroxyurea
- hydroxyzine
- hydrozoan
- Hydrus
- hyena