English Words Starting With O

• opalescence

  nounC1
  /ˌəʊ.pəlˈes.əns/The quality of reflecting an iridescent, milky light with shifting colours, like an opal.
• opaleye

  nounVery Low
  /ˈəʊp(ə)lʌɪ/A type of sea fish characterised by distinctive opalescent eyes.
• opaline

  adjectivenounLow
  /ˈəʊ.pə.laɪn/Adjective: having the milky, iridescent appearance or colours of an opal.
• opaque

  adjectivenounverbverb-transitiveC1
  /əʊˈpeɪk/Not allowing light to pass through; impossible to see through.
• opaque context

  nounC2
  /əʊˈpeɪk ˈkɒn.tekst/A linguistic or philosophical situation where substitution of co-referential terms changes truth value, making meaning or reference non-transparent.
• opaque projector

  nounC2
  /əʊˌpeɪk prəˈdʒɛktə/A device that projects enlarged images of opaque materials (e.g., books, drawings, solid objects) onto a screen by using a strong internal light source and a system of mirrors and lenses.
• ope

  adjectiveverbVery Low
  /əʊp/An archaic or poetic verb meaning 'open'.
• opec

  acronymnounC1
  /ˈəʊpek/An international organization of major oil-producing countries that coordinates and unifies petroleum policies among its members.
• opechancanough

  nounExtremely Rare
  /ˌɒpɪˈtʃænkənuː/The name of a prominent 16th/17th-century Native American tribal chief of the Powhatan Confederacy in what is now Virginia, USA.
• opelika

  nounVery Low
  /ˌəʊ.pəˈliː.kə/A proper noun referring to a city in eastern Alabama, United States.
• opelousas

  nounVery Low
  /ˌəʊ.pəˈluː.səs/A proper noun referring to a city in the U.S. state of Louisiana.
• open

  adjectivenounverbverb-intransitiveverb-transitiveA1
  /ˈəʊp(ə)n/To move a door, lid, or container so that access is possible; not closed or sealed.
• open account

  nounB2
  /ˌəʊ.pən əˈkaʊnt/To establish a formal financial arrangement with a bank or institution, allowing deposits, withdrawals, and other transactions.
• open admissions

  nounMedium
  /ˌəʊpən ədˈmɪʃənz/A policy in higher education where a college or university accepts all applicants who have completed high school, regardless of academic qualifications.
• open adoption

  nounMedium (specialised)
  /ˌəʊ.pən əˈdɒp.ʃən/An adoption arrangement where the birth family and adoptive family have some form of contact and exchange of information, which can range from letters to direct meetings.
• open air

  nounB1
  /ˌəʊ.pən ˈeər/The natural outdoor atmosphere, not inside any building or shelter.
• open bar

  nounC1
  /ˌəʊ.pən ˈbɑː(r)/An event where all alcoholic drinks are provided free of charge to guests, typically for a limited time.
• open book

  nounB2
  /ˌəʊ.pən ˈbʊk/A person or situation that is easy to understand or about which there are no secrets.
• open brethren

  nounVery Low (Specialized)
  /ˌəʊpən ˈbrɛðrən/A collective term for a specific group within the Plymouth Brethren, a conservative, non-denominational Christian movement, characterized by a policy of openness in communion, allowing non-members to participate in the Lord's Supper.
• open call

  nounB2
  /ˌəʊ.pən ˈkɔːl/A public invitation for applications or auditions, where anyone meeting the basic criteria may apply or participate.

Showing 1321–1340 of 3187 words.