- Octal Adj Noun
- Octamer Noun
- Octameter Noun
- Octanal Noun
- Octane Noun
- Octanol Noun
- Octanoyl Noun
- Octant Noun
- Octarchy Noun
- Octastich Noun
- Octastyle Adj Noun
- Octateuch Noun
- Octave Noun
- Octavia Noun
- Octavo Noun
- Octene Noun
- Octennial Adj Noun
- Octet Noun
- Octile Noun
- Octillion Noun
- October Noun
- Octobrist Noun
- Octocentenary Noun Adj
- Octodecimo Noun
- Octodenary Adj Noun
- Octofluorocyclobutane Noun
- Octofoil Noun
- Octogenarian Adj Noun
- Octonary Adj Noun
- Octophobia Noun
- Octoploid Adj Noun
- Octopod Noun
- Octopole Noun
- Octopus Noun
- Octoroon Noun
- Octosyllable Noun
- Octree Noun
- Octroi Noun
- Octroy Noun Verb
- Octuple Adj Noun Verb
- Octuplets Noun
- Octuplicate Adj Noun Verb
- Octupling Noun
- Octyl Adj Noun
- Octyne Noun
- Ocularist Noun
- Oculist Noun
- Oculistics Noun
- Oculography Noun
- Oculometry Noun
- Oculomotor Noun Adj
- Oculomycosis Noun
- Oculomyodynamometry Noun
- Oculopathy Noun
- Oculoplastics Noun
- Oculoplethysmography Noun
- Oculopneumoplethysmography Noun
- Oculopressor Noun
- Oculus Noun
- Odalisque Noun