1. graded adjective & adjective If you are unaccustomed to something, you do not know it very well or have not experienced it very often. [written] [+ to] ⇒ They were unaccustomed to such military setbacks. [+ to] ⇒ It is a part of Britain as yet largely unaccustomed to tourists. 2. graded adjective & adjective [ADJ n] If you describe someone's behaviour or experiences as unaccustomed, you mean that they do not usually behave like this or have experiences of this kind. [written] ⇒ He began to comfort me with such unaccustomed gentleness. ⇒ His nose had been reddened by unaccustomed exposure to the California sun.
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