thun·der·head 
(thŭndər-hĕd′)
(thŭndər-hĕd′)n.
The swollen upper portion of a thundercloud, usually associated with the development of a thunderstorm.
- heave into sight/view
- heave into view
- heaven
- heavenliness
- heavenly
- heaven-sent
- heavenward
- heavenwards
- heaver
- heave to
- heavier-than-air
- heavily
- heaviness
- Heaviside layer
- heavy
- heavy chain
- heavy-duty
- heavy-footed
- heavy-handed
- heavy-handedness
- heavy-hearted
- heavy-heartedly
- heavy-heartedness
- heavy hitter
- heavy hydrogen