English Words Starting With O

• ophiuchus

  nounRare
  /ˌɒfɪˈjuːkəs/A large constellation located around the celestial equator, depicted as a man grasping a serpent.
• ophiuroid

  adjectivenounRare/Very low
  /ˌɒfɪˈjʊərɔɪd/A marine invertebrate animal belonging to the class Ophiuroidea, closely related to starfish and commonly known as a brittle star or serpent star.
• ophthalmia

  nounRare
  /ɒfˈθæl.mi.ə/Severe inflammation of the eye, particularly the conjunctiva.
• ophthalmia neonatorum

  nounVery Low
  /ˌɒfˈθælmiə ˌniːəʊnəˈtɔːrəm/A severe form of conjunctivitis affecting newborns.
• ophthalmic optician

  nounC1
  /ɒfˌθæl.mɪk ɒpˈtɪʃ.ən/A healthcare professional who is qualified to examine the eyes, detect vision defects and eye diseases, and prescribe and fit corrective lenses.
• ophthalmitis

  nounVery Low
  /ˌɒf.θælˈmaɪ.tɪs/A medical term for inflammation of the eye.
• ophthalmodynamometer

  nounExtremely rare
  /ˌɒfθælməʊˌdaɪnəˈmɒmɪtə(r)/A medical instrument used to measure the blood pressure in the retinal arteries of the eye.
• ophthalmologist

  nounC1
  /ˌɒf.θælˈmɒl.ə.dʒɪst/A medical doctor who specializes in diagnosing, treating, and preventing diseases and injuries of the eye and visual system.
• ophthalmology

  nounC1/C2
  /ˌɒf.θælˈmɒl.ə.dʒi/The branch of medicine and surgery concerned with the study, diagnosis, and treatment of diseases and disorders of the eye.
• ophthalmometer

  nounC2
  /ˌɒfθælˈmɒmɪtə/An instrument for measuring the refractive errors of the eye and the curvature of the cornea.
• ophthalmoscope

  nounLow
  /ɒfˈθæl.mə.skəʊp/A medical instrument for examining the interior of the eye.
• ophthalmoscopy

  nounVery low
  /ˌɒf.θælˈmɒs.kə.pi/The examination of the interior of the eye using an instrument called an ophthalmoscope.
• ophuls

  nounVery Low
  /ˈɒfʊlz/A proper noun; specifically, a surname associated with the notable German-born film director Max Ophüls, known for his visually intricate, romantic melodramas.
• opiate

  adjectivenounverbverb-transitiveC1/C2
  /ˈəʊ.pi.ət/A drug containing opium or an opioid, used to relieve pain or induce sleep.
• opine

  verbverb-ambitransitiveC2 - Very Low Frequency
  /əʊˈpaɪn/To express one's opinion formally, especially in a considered, expert, or didactic manner.
• opined

  adjectiveverbC1-C2 / Low
  /əʊˈpaɪnd/To formally express one's opinion, often in a thoughtful or authoritative manner.
• opinicus

  nounVery rare
  /əʊˈpɪnɪkəs/A mythical heraldic beast, often depicted as a hybrid creature, resembling a winged lion or griffin, used primarily in heraldic contexts.
• opinion

  nounA1 (Very High)
  /əˈpɪnjən/A personal view, judgment, or belief about something, not necessarily based on fact or knowledge.
• opinion poll

  nounC1
  /əˈpɪnjən pəʊl/A survey of public opinion on a particular topic or set of topics.
• opioid

  adjectivenounC1
  /ˈəʊ.pi.ɔɪd/Any of a class of drugs, both natural and synthetic, that bind to opioid receptors in the brain, producing analgesic (pain-relieving) and often euphoric effects.

Showing 1481–1500 of 3187 words.