Collins COBUILD Advanced Learner’s Dictionary

3 ADJ [ADJ after v] If you do something unchallenged , nobody stops you and asks you questions, for example about who you are or why you are doing it. □  I managed to walk around unchallenged for 10 minutes before an alert nurse spotted me.

un|change|able /ʌ ntʃe I ndʒəb ^ə l/ ADJ Something that is unchangeable cannot be changed at all. □  The doctrine is unchangeable. □  …a thoroughly organised and almost unchangeable system of laws and customs.

un|changed /ʌ ntʃe I ndʒd/ ADJ [usu v-link ADJ ] If something is unchanged , it has stayed the same for a particular period of time. □  For many years prices have remained virtually unchanged.

un|chang|ing /ʌ ntʃe I ndʒ I ŋ/ ADJ Something that is unchanging always stays the same. □  …eternal and unchanging truths.

un|char|ac|ter|is|tic /ʌ nkær I ktər I st I k/ ADJ If you describe something as uncharacteristic of someone, you mean that it is not typical of them. □ [+ of ] It was uncharacteristic of her father to disappear like this. □  …an uncharacteristic lack of modesty. ●  un|char|ac|ter|is|ti|cal|ly /ʌ nkær I ktər I st I kli/ ADV [usu ADV adj, oft ADV with v] □  Owen has been uncharacteristically silent. □  Uncharacteristically for him, he decided to have a snooze.

un|chari|table /ʌ ntʃæ r I təb ^ə l/ ADJ If you describe someone's remarks, thoughts, or behaviour as uncharitable , you think they are being unkind or unfair to someone. □  This was an uncharitable assessment of the reasons for the failure.

un|chart|ed /ʌ ntʃɑː ^r t I d/ ADJ [usu ADJ n] If you describe a situation, experience, or activity as uncharted territory or waters, you mean that it is new or unfamiliar. □  Carter's fourth album definitely moves into uncharted territory. □  …a largely uncharted area of medical science.

un|checked /ʌ ntʃe kt/ ADJ [ADJ after v, ADJ n, v-link ADJ ] If something harmful or undesirable is left unchecked , nobody controls it or prevents it from growing or developing. □  If left unchecked, weeds will flourish. □  …a world in which brutality and lawlessness are allowed to go unchecked.

un|civi|lized /ʌ ns I v I la I zd/ in BRIT, also use uncivilised ADJ If you describe someone's behaviour as uncivilized , you find it unacceptable, for example because it is very cruel or very rude. [DISAPPROVAL ] □  The campaign has abounded in mutual accusations of uncivilised behaviour. □  I think sport involving animals is barbaric and uncivilized.

un|claimed /ʌ nkle I md/ ADJ If something is unclaimed , nobody has claimed it or said that it belongs to them. □  Her luggage remained unclaimed at Frankfurt Departures. □  …unclaimed prizes.

un|clas|si|fied /ʌ nklæ s I fa I d/

1 ADJ If information or a document is unclassified , it is not secret and is available to the general public.

2 ADJ If something is unclassified , it has not been given a grade or put into a category, for example because it is of a low or basic standard. □  …an unclassified honours degree.

un|cle ◆◆◇ /ʌ ŋk ^ə l/ (uncles ) N‑COUNT ; N‑TITLE Someone's uncle is the brother of their mother or father, or the husband of their aunt. □  My uncle was the mayor of Memphis. □  A text from Uncle Fred arrived.

un|clean /ʌ nkliː n/

1 ADJ Something that is unclean is dirty and likely to cause disease. □  …the Western attitude to insects as being dirty and unclean. □  By bathing in unclean water, they expose themselves to contamination.