1. Without bounds
   - immeasurably, infinitely

See also: boundless

• operon
• operose
• operoseness
• Opheodrys
• Opheodrys aestivus
• Opheodrys vernalis
• Ophidia
• ophidian
• Ophidiidae
• ophidism
• Ophiodon
• Ophiodon elongatus
• Ophiodontidae
• Ophioglossaceae
• Ophioglossales
• Ophioglossum
• Ophioglossum pendulum
• ophiolatry
• Ophiophagus
• Ophiophagus hannah
• Ophisaurus
• ophite
• Ophiuchus
• Ophiurida
• Ophiuroidea