Ibn al-Hay·tham 
(ĭb′ən ĕl-hīthəm) Full name Abu Ali al-Hasan Ibn al-Haytham. Also known as Al·haz·en (ăl-hăzən) 965?-1040?
(ĭb′ən ĕl-hīthəm) Full name Abu Ali al-Hasan Ibn al-Haytham. Also known as Al·haz·en (ăl-hăzən) 965?-1040? Arab mathematician and astronomer best known for his book on optics, which presented experimental studies of reflection and refraction and an influential theory of vision that revised that of the Greeks.
- ground bass
- ground beetle
- groundbreaker
- groundbreaking
- ground cedar
- ground cherry
- ground cloth
- ground-controlled approach
- ground cover
- groundcover
- ground crew
- ground-effect machine
- grounder
- ground fault
- ground-fault interrupter
- groundfish
- ground floor
- ground glass
- ground hemlock
- groundhog
- ground hog
- Groundhog Day
- ground ivy
- groundkeeper
- groundkeeper