op|ti|mum /ɒ pt I məm/ or optimal ADJ [usu ADJ n] The optimum or optimal level or state of something is the best level or state that it could achieve. [FORMAL ] □ Aim to do some physical activity three times a week for optimum health. □ …regions in which optimal conditions for farming can be created.
op|tion ◆◆◇ /ɒ pʃ ə n/ (options )
1 N‑COUNT An option is something that you can choose to do in preference to one or more alternatives. □ He's argued from the start that America and its allies are putting too much emphasis on the military option. □ What other options do you have?
2 N‑SING [N to-inf] If you have the option of doing something, you can choose whether to do it or not. □ [+ of ] Criminals are given the option of going to jail or facing public humiliation. □ We had no option but to abandon the meeting.
3 N‑COUNT In business, an option is an agreement or contract that gives someone the right to buy or sell something such as property or shares at a future date. [BUSINESS ] □ Each bank has granted the other an option on 19.9% of its shares.
4 N‑COUNT An option is one of a number of subjects which a student can choose to study as a part of his or her course. □ Several options are offered for the student's senior year.
5 PHRASE If you keep your options open or leave your options open , you delay making a decision about something. □ I am keeping my options open. I have not made a decision on either matter.
6 PHRASE If you take the soft option , you do the thing that is easiest or least likely to cause trouble in a particular situation. [mainly BRIT ] □ The job of chairman can no longer be regarded as a convenient soft option. COLLOCATIONS option NOUN 1
noun + option : career, treatment
adjective + option : attractive, cheap, easy, healthy; available, safe, viable
verb + option : choose, exercise, select; consider, discuss, explore SYNONYMS option NOUN 1
alternative: New ways to treat arthritis may provide an alternative to painkillers.
choice: You've got three choices: small, medium or large.
op|tion|al /ɒ pʃən ə l/ ADJ If something is optional , you can choose whether or not you do it or have it. □ Sex education is a sensitive area for some parents, and thus it should remain optional.
op|tom|etrist /ɒptɒ mətr I st/ (optometrists ) N‑COUNT An optometrist is the same as an optician . [mainly AM ] in BRIT, usually use optician
o pt-out (opt-outs )
1 ADJ [ADJ n] An opt-out school or hospital has chosen to leave local government control and manage itself using national government money. [BRIT ] □ …teachers at opt-out schools.
2 N‑COUNT You can refer to the action taken by a school or hospital in which they choose not to be controlled by a local government authority as an opt-out . [BRIT ] □ More freedom and choice will be given to parents, and the school opt-outs will be stepped up.
3 ADJ [ADJ n] An opt-out clause in an agreement gives people the choice not to be involved in one part of that agreement. [mainly BRIT ] □ …an opt-out clause.
4 N‑COUNT You can refer to the action of choosing not to be involved in a particular part of an agreement as an opt-out . □ …a list of demands, such as opt-outs from some parts of the treaty.
opu|lent /ɒ pjʊlənt/
1 ADJ Opulent things or places look grand and expensive. [FORMAL ] □ …an opulent office on Wimpole Street in London's West End. ● opu|lence N‑UNCOUNT □ [+ of ] …the elegant opulence of the German embassy.
2 ADJ [usu ADJ n] Opulent people are very wealthy and spend a lot of money. [FORMAL ] □ Most of the cash went on supporting his opulent lifestyle.
opus /oʊ pəs, ɒ pəs/ (opuses or opera )
1 N‑COUNT An opus is a piece of classical music by a particular composer. Opus is usually followed by a number which indicates at what point the piece was written. The abbreviation op. is also used. □ …Beethoven's Piano Sonata in E minor, Opus 90.
2 N‑COUNT You can refer to an artistic work such as a piece of music or writing or a painting as an opus . □ …the new opus from Peter Gabriel.
3 → see also magnum opus
or ◆◆◆ /ə r , STRONG ɔː r /
1 CONJ You use or to link two or more alternatives. □ 'Tea or coffee?' John asked. □ He said he would try to write or call as soon as he reached the Canary Islands. □ Students are asked to take another course in English, or science, or mathematics.
2 CONJ You use or to give another alternative, when the first alternative is introduced by 'either' or 'whether'. □ Items like bread, milk and meat were either unavailable or obtained only on the black market. □ Either you can talk to him, or I will. □ I don't know whether people will buy it or not.
3 CONJ You use or between two numbers to indicate that you are giving an approximate amount. □ Everyone benefited from limiting their intake of tea to just three or four cups a day. □ Normally he asked questions, and had a humorous remark or two.
4 CONJ You use or to introduce a comment which corrects or modifies what you have just said. □ The man was a fool, he thought, or at least incompetent. □ There was nothing more he wanted, or so he thought.
5 CONJ If you say that someone should do something or something unpleasant will happen, you are warning them that if they do not do it, the unpleasant thing will happen. □ She had to have the operation, or she would die.