Collins COBUILD Advanced Learner’s Dictionary

un|know|ing|ly /ʌ nnoʊ I ŋli/ ADV [ADV with v] If someone does something unknowingly , they do it without being aware of it. □  …if people unknowingly move into more contaminated areas of the river. □  You may be contributing unknowingly to the suffering of animals.

un|known ◆◇◇ /ʌ nnoʊ n/ (unknowns )

1 ADJ If something is unknown to you, you have no knowledge of it. □  An unknown number of demonstrators were arrested. □  How did you expect us to proceed on such a perilous expedition, through unknown terrain? □  The motive for the killing is unknown. ● N‑COUNT An unknown is something that is unknown. □  The length of the war is one of the biggest unknowns.

2 ADJ An unknown person is someone whose name you do not know or whose character you do not know anything about. □  Unknown thieves had forced their way into the apartment. □ [+ to ] I could not understand how someone with so many awards could be unknown to me.

3 ADJ An unknown person is not famous or publicly recognized. □  He was an unknown writer. □  …a popular environment where both established and unknown artists can meet, talk and drink. ● N‑COUNT An unknown is a person who is unknown. □  How had he, a complete unknown, achieved this transformation?

4 ADJ [usu v-link ADJ ] If you say that a particular problem or situation is unknown , you mean that it never occurs. □  Diabetes is virtually unknown in poorer countries.

5 N‑SING The unknown refers generally to things or places that people do not know about or understand. □  Ignorance of people brings fear, fear of the unknown.

un|law|ful /ʌ nlɔː fʊl/ ADJ If something is unlawful , the law does not allow you to do it. [FORMAL ] □  …employees who believe their dismissal was unlawful. □  A pushed-in window indicated unlawful entry. ●  un|law|ful|ly ADV [ADV with v] □  …the councils' assertion that the government acted unlawfully in imposing the restrictions.

u n|law|ful ki ll|ing (unlawful killings ) N‑VAR Unlawful killing is used to refer to crimes which involve one person killing another. [LEGAL ]

un|lead|ed /ʌ nle d I d/ ADJ Unleaded fuel contains a smaller amount of lead than most fuels so that it produces fewer harmful substances when it is burned. □  This model is designed to run on unleaded fuel. ● N‑UNCOUNT Unleaded is also a noun. □  All its engines will run happily on unleaded.

un|learn /ʌ nlɜː ^r n/ (unlearns , unlearning , unlearned ) in BRIT, also use unlearnt VERB If you unlearn something that you have learned, you try to forget it or ignore it, often because it is wrong or it is having a bad influence on you. □ [V n] They learn new roles and unlearn old ones. □ [V n] Before you know it, you will have unlearned the debt habit.

un|leash /ʌ nliː ʃ/ (unleashes , unleashing , unleashed ) VERB If you say that someone or something unleashes a powerful force, feeling, activity, or group, you mean that they suddenly start it or send it somewhere. □ [V n] Then he unleashed his own, unstoppable, attack. □ [V n] The officers were still reluctant to unleash their troops in pursuit of a defeated enemy.

un|leav|ened /ʌ nle v ^ə nd/ ADJ [usu ADJ n] Unleavened bread or dough is made without any yeast.