English English
CEFR LEVEL
3335 entries have no recorded CEFR level and are included in All.
Oar
word C1a long pole with a flat blade used to propel and steer a boat through water by manual rowing
↗obliterate
word C1to destroy completely; to remove all traces of something; To destroy utterly; wipe out completely, to erase or remove something completely.; Destroy utterly; wipe out completely.
↗Oblivion
word C1the state of being completely forgotten; unconsciousness; complete forgetfulness
↗oblivious
word C1Not aware of or concerned about what is happening around oneself.
↗obstinate
word C1Stubbornly refusing to change one's opinion or chosen course of action, despite attempts to persuade one to do so.
↗occult
word C1Relating to mysterious, supernatural, or magical powers and practices.
↗ocean acidification
word C1The continuous reduction in pH levels of Earth's oceans caused by the uptake of anthropogenic carbon dioxide from the atmosphere.
↗odyssey
word C1A long and eventful or adventurous journey.
↗oligarchy
word C1A small group of people having control of a country, organization, or institution.
↗omission
word C1The action of excluding or leaving out someone or something; a failure to include.; someone or something that has been left out or excluded the action of excluding or leaving out someone or something; a failure to include The act of leaving out or excluding something; something that has been left out.
↗omnipresent
word C1Present everywhere at the same time; widely or constantly encountered.
↗onerous
word C1Involving a great deal of effort, difficulty, or burdensome responsibility.
↗open up
phrasal verb C1To create new opportunities, or to speak freely and candidly; to speak freely or openly about one's feelings; to make available or accessible
↗optimization
word C1The action of making the best or most effective use of a situation or resource.
↗optimize
word C1To make the best or most effective use of a situation, opportunity, or resource.
↗optimized
word C1Made as effective, functional, or efficient as possible.
↗optimum
word C1Most favorable, advantageous, or conducive to a desired outcome; best.
↗oratory
word C1The art or practice of formal public speaking, especially in an eloquent and persuasive manner.
↗orchestrate
word C1To plan, arrange, or coordinate the elements of a situation to achieve a desired result, often secretly.
↗ordeal
word C1a very painful, severe, or difficult experience
↗oscillate
word C1To swing back and forth steadily, or waver between different opinions or states.
↗ostentatious
word C1Characterized by pretentious or showy display designed to impress others.
↗Outwardly
word C1on the surface; externally; in appearance
↗overarching
word C1Comprehensive or all-embracing; dominating or encompassing everything.
↗overcrowding
word C1The presence of more people or things in a space than is comfortable, safe, or permissible.
↗overgrazing
word C1The excessive grazing of pasture by livestock to the point where vegetative cover is destroyed and soil eroded.
↗overstimulated
word C1Excessively agitated or overwhelmed by too much sensory or cognitive stimulation.
↗oxidation
word C1The process or result of oxidizing; a chemical reaction in which a substance gains oxygen or loses electrons.
↗oxidative
word C1Relating to or involving oxidation, particularly processes that can cause cellular damage through free radicals.
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