defence：防御，防卫，保卫；辩护，答辩；(复数)防御工事

词根词缀：de-离开 + -fenc-打击 + -e

• operatic
• operation
• operational
• operative
• operatize
• operator
• operetta
• operose
• ophidophobia
• ophthalmic
• ophthalmo-
• ophthalmologist
• ophthalmology
• opiate
• opine
• opinion
• opinionated
• opinionist
• opium
• opossum
• opponent
• opportune
• opportunism
• opportunist
• opportunity