English Words Starting With O

• oxybenzene

  nounVery low/Very technical
  /ˌɒksɪˈbɛnziːn/Another name for phenol, a white crystalline compound with a distinct odour, used as a disinfectant and in chemical synthesis.
• oxycalcium light

  nounExtremely Low
  /ˌɒksɪˈkælsiəm ˌlaɪt/A very bright light produced by directing an oxygen-rich flame onto a block of quicklime (calcium oxide).
• oxycellulose

  nounC2
  /ˌɒksiˈsɛljʊləʊz/A chemically modified cellulose (a polysaccharide) that has been oxidized, typically through treatment with nitric acid or other oxidizing agents.
• oxycephaly

  nounVery Low / Highly Specialized
  /ˌɒksɪˈsɛfəli/A congenital deformity of the skull characterized by a pointed or cone-shaped head.
• oxychloride

  nounC2
  /ˌɒksɪˈklɔːrʌɪd/A chemical compound containing both oxygen and chlorine atoms bonded to another element, typically a metal.
• oxycodone

  nounC2
  /ˌɒksɪˈkəʊdəʊn/A powerful semi-synthetic opioid analgesic medication.
• oxycodone hydrochloride

  nounLow
  /ˌɒk.sɪˈkəʊ.dəʊn ˌhaɪ.drəʊˈklɔː.raɪd/The salt form of the semi-synthetic opioid analgesic oxycodone, used for moderate to severe pain.
• oxycontin

  nounLow
  /ˌɒk.siˈkɒn.tɪn/A proprietary brand name for oxycodone hydrochloride, a powerful, extended-release prescription opioid pain medication.
• oxygen

  nounC1
  /ˈɒk.sɪ.dʒən/A colourless, odourless, gaseous chemical element (symbol O, atomic number 8) essential for respiration and combustion, constituting about 21% of the Earth's atmosphere.
• oxygen acid

  nounLow (C2)
  /ˈɒksɪdʒən ˈæsɪd/An acid whose molecules contain oxygen atoms bonded to hydrogen and another element (usually a nonmetal). A synonym for oxyacid.
• oxygen bar

  nounLow
  /ˈɒksɪdʒən ˌbɑː/A commercial establishment where customers pay to inhale oxygen, often with added scents, for supposed health or recreational benefits.
• oxygen cycle

  nounLow
  /ˈɒksɪdʒən ˈsaɪk(ə)l/The biogeochemical cycle that describes the movement and transformation of oxygen within and between the Earth's atmosphere, lithosphere, biosphere, and hydrosphere.
• oxygen debt

  nounC1
  /ˈɒksɪdʒ(ə)n dɛt/The temporary deficit in oxygen levels within the body's tissues, particularly muscles, that occurs during intense or anaerobic exercise, requiring a period of heavier breathing to 'repay'.
• oxygen effect

  nounC2
  /ˈɒksɪdʒən ɪˈfɛkt/The phenomenon in radiation biology where the presence of oxygen makes cells more sensitive to the damaging effects of ionizing radiation.
• oxygen lance

  nounC2 / Extremely Low
  /ˈɒksɪdʒən lɑːns/A long tube used to deliver a high-pressure stream of oxygen, typically for industrial cutting, piercing, or refining of metal.
• oxygen mask

  nounC1
  /ˈɒksɪdʒən mɑːsk/A device covering the nose and mouth, connected to an oxygen supply, allowing a person to breathe when air quality is poor or oxygen levels are low.
• oxygen tent

  nounLow
  /ˈɒk.sɪ.dʒən tent/A canopy placed over a bed to deliver a controlled, oxygen-rich environment for medical treatment.
• oxygen weed

  nounLow
  /ˈɒksɪdʒən wiːd/A common name for any of several fast-growing aquatic plants, particularly invasive ones, that produce large amounts of oxygen and can form dense mats on the surface of the water.
• oxygenase

  nounLow
  /ˈɒksɪdʒəneɪz/An enzyme that catalyses the incorporation of molecular oxygen into a substrate.
• oxygenate

  verbverb-transitiveC1
  /ˈɒk.sɪ.dʒə.neɪt/To supply, treat, or combine with oxygen.

Showing 3101–3120 of 3187 words.