Collins COBUILD Advanced Learner’s Dictionary

A lev|el /e I lev ^ə l/ (A levels ) N‑VAR A levels are British educational qualifications which school children take when they are seventeen or eighteen years old. People usually need A levels if they want to go to university in Britain. □  He left school with four A levels.

al|fal|fa /ælfæ lfə/ N‑UNCOUNT Alfalfa is a plant that is used for feeding farm animals. The shoots that develop from its seeds are sometimes eaten as a vegetable.

al|fres|co /ælfre skoʊ/ also al fresco ADJ [ADJ n] An alfresco activity, especially a meal, is one that takes place in the open air. □  … an al fresco breakfast of fresh fruit. ● ADV [ADV after v] Alfresco is also an adverb. □  He came across the man shaving alfresco.

al|gae /æ ldʒi, æ lga I / N‑UNCOUNT [with sing or pl verb] Algae is a type of plant with no stems or leaves that grows in water or on damp surfaces.

al|gal /æ lgəl/ ADJ [ADJ n] Algal means relating to algae. □  Sewage nutrients do increase algal growth in the harbour.

al|ge|bra /æ ldʒ I brə/ N‑UNCOUNT Algebra is a type of mathematics in which letters are used to represent possible quantities. WORD HISTORY algebra

The term al-jabr is taken from the title of a ninth-century Arabic book on mathematics. In Arabic, al-jabr means 'reunion' or 'integration'. When the book was later translated into Latin, al-jabr became algebra .

al|ge|bra|ic /æ ldʒ I bre I I k/ ADJ [ADJ n] Algebraic equations, expressions, and principles are based on or use algebra.

Al|ge|rian /æ ldʒ I ə riən/ (Algerians )

1 ADJ Algerian means belonging or relating to Algeria, or its people or culture. □  …the Algerian desert. □  …a young Algerian actor.

2 N‑COUNT An Algerian is an Algerian citizen or a person of Algerian origin.

al|go|rithm /æ lgər I ðəm/ (algorithms ) N‑COUNT An algorithm is a series of mathematical steps, especially in a computer program, which will give you the answer to a particular kind of problem or question.

alia /e I liə/ → see inter alia

ali|as /e I liəs/ (aliases )

1 N‑COUNT An alias is a false name, especially one used by a criminal. □  Using an alias, he had rented a house in Fleet, Hampshire.

2 PREP You use alias when you are mentioning another name that someone, especially a criminal or an actor, is known by. □  …the defendant Pericles Pericleous, alias Peter Smith.

ali|bi /æ l I ba I / (alibis ) N‑COUNT If you have an alibi , you can prove that you were somewhere else when a crime was committed.

al|ien /e I liən/ (aliens )

1 ADJ [usu ADJ n] Alien means belonging to a different country, race, or group, usually one you do not like or are frightened of. [FORMAL , DISAPPROVAL ] □  He said they were opposed to the presence of alien forces in the region.

2 ADJ [usu ADJ n] You use alien to describe something that seems strange and perhaps frightening, because it is not part of your normal experience. □  His work offers an insight into an alien culture.

3 ADJ If something is alien to you or to your normal feelings or behaviour, it is not the way you would normally feel or behave. [FORMAL ] □ [+ to ] Such an attitude is alien to most businessmen.

4 N‑COUNT An alien is someone who is not a legal citizen of the country in which they live. [FORMAL , LEGAL ]

5 N‑COUNT In science fiction, an alien is a creature from outer space.

al|ien|ate /e I liəne I t/ (alienates , alienating , alienated )

1 VERB If you alienate someone, you make them become unfriendly or unsympathetic towards you. □ [V n] The government cannot afford to alienate either group.

2 VERB To alienate a person from someone or something that they are normally linked with means to cause them to be emotionally or intellectually separated from them. □ [V n + from ] His second wife, Alice, was determined to alienate him from his two boys.

alight /əla I t/ (alights , alighting , alighted )

1 ADJ [v-link ADJ ] If something is alight , it is burning. □  Several buildings were set alight.