竹芋属：热带草本植物之一属，有几种的根可产淀粉，供作撒布粉和润滑药- orthodontics
- orthodontist
- orthodontology
- orthodromic
- orthogenesis
- orthogenics
- orthoglycemic
- Orthognatha
- orthognathia
- orthognathic
- orthognathous
- orthograde
- orthomelic
- orthometer
- orthomolecular
- orthomorphia
- orthomyxovirus
- orthoneutrophil
- orthopaedic
- orthopaedics
- orthopantograph
- Orthopantomograph
- orthopedic
- orthopedics
- orthopedist