op|pres|sion /əpre ʃ ə n/ N‑UNCOUNT Oppression is the cruel or unfair treatment of a group of people. □ …an attempt to escape political oppression. [Also + of ]
op|pres|sive /əpre s I v/
1 ADJ If you describe a society, its laws, or customs as oppressive , you think they treat people cruelly and unfairly. □ The new laws will be just as oppressive as those they replace. □ …refugees from the oppressive regime.
2 ADJ If you describe the weather or the atmosphere in a room as oppressive , you mean that it is unpleasantly hot and damp. □ The oppressive afternoon heat had quite tired him out.
3 ADJ [usu ADJ n] An oppressive situation makes you feel depressed and uncomfortable. □ …the oppressive sadness that weighed upon him like a physical pain.
op|pres|sor /əpre sə r / (oppressors ) N‑COUNT [oft with poss] An oppressor is a person or group of people that is treating another person or group of people cruelly or unfairly. □ Lacking sovereignty, they could organise no defence against their oppressors.
op|pro|brium /əproʊ briəm/ N‑UNCOUNT Opprobrium is open criticism or disapproval of something that someone has done. [FORMAL ] □ [+ of ] His political opinions have attracted the opprobrium of the Left.
opt ◆◇◇ /ɒ pt/ (opts , opting , opted ) VERB If you opt for something, or opt to do something, you choose it or decide to do it in preference to anything else. □ [V + for ] Depending on your circumstances you may wish to opt for one method or the other. □ [V to-inf] Our students can also opt to stay in residence.
▸ opt in PHRASAL VERB If you can opt in to something, you are able to choose to be part of an agreement or system. □ [V P + to ] He proposed that only those countries which were willing and able should opt in to phase three. □ [V P ] He didn't exactly opt out because he never opted in.
▸ opt out PHRASAL VERB If you opt out of something, you choose to be no longer involved in it. □ [V P + of ] … powers for hospitals to opt out of health authority control. □ [V P ] Under the agreement the Vietnamese can opt out at any time.
op|tic /ɒ pt I k/
1 ADJ [ADJ n] Optic means relating to the eyes or to sight. □ The reason for this is that the optic nerve is a part of the brain.
2 → see also optics
op|ti|cal /ɒ pt I k ə l/ ADJ [usu ADJ n] Optical devices, processes, and effects involve or relate to vision, light, or images. □ …optical telescopes. □ …the optical effects of volcanic dust in the stratosphere.
o p|ti|cal fi |bre (optical fibres ) in AM, use optical fiber N‑VAR An optical fibre is a very thin thread of glass inside a protective coating. Optical fibres are used to carry information in the form of light.
o p|ti|cal il|lu |sion (optical illusions ) N‑COUNT An optical illusion is something that tricks your eyes so that what you think you see is different from what is really there. □ Sloping walls on the bulk of the building create an optical illusion.
op|ti|cian /ɒpt I ʃ ə n/ (opticians )
1 N‑COUNT An optician is someone whose job involves testing people's sight, and making or selling glasses and contact lenses.
2 N‑COUNT An optician or an optician's is a shop where you can have your eyes tested and buy glasses and contact lenses. □ Some may need specialist treatment at the optician's.
op|tics /ɒ pt I ks/
1 N‑UNCOUNT Optics is the branch of science concerned with vision, sight, and light.
2 → see also fibre optics
op|ti|mal /ɒ pt I m ə l/ → see optimum
op|ti|mism /ɒ pt I m I zəm/ N‑UNCOUNT Optimism is the feeling of being hopeful about the future or about the success of something in particular. □ The manager expressed optimism about adding to his squad before the transfer window closes. □ …a mood of cautious optimism.
op|ti|mist /ɒ pt I m I st/ (optimists ) N‑COUNT An optimist is someone who is hopeful about the future. □ Optimists reckon house prices will move up with inflation this year.
op|ti|mis|tic ◆◇◇ /ɒ pt I m I st I k/ ADJ [ADJ that] Someone who is optimistic is hopeful about the future or the success of something in particular. □ The President says she is optimistic that an agreement can be worked out soon. □ Michael was in a jovial and optimistic mood. [Also + about ] ● op|ti|mis|ti|cal|ly ADV [ADV with v] □ Both sides have spoken optimistically about the talks. SYNONYMS optimistic ADJ 1
hopefuclass="underline" Surgeons were hopeful of saving the sight in Sara's left eye.
positive: Be positive about your future and get on with living a normal life.
bright: The boy was so bright and animated.
cheerfuclass="underline" Jack sounded quite cheerful about the idea.
op|ti|mize /ɒ pt I ma I z/ (optimizes , optimizing , optimized ) in BRIT, also use optimise 1 VERB To optimize a plan, system, or machine means to arrange or design it so that it operates as smoothly and efficiently as possible. [FORMAL ] □ [be V -ed] The new systems have been optimised for running Microsoft Windows.
2 VERB To optimize a situation or opportunity means to get as much advantage or benefit from it as you can. [FORMAL ] □ [V n] What can you do to optimize your family situation?