closed-book
adj1
Education Designating an examination in which external resources such as calculators, glossaries, and study notes are prohibited.
- Antonyms
- open-book
- Coordinate terms
- take-home
closed book
nounalso spelled closed-book1
Idiomatic A person or thing that cannot be easily understood; someone or something incomprehensible or puzzling.
- Her courteous, sedate, inexorable husband, whose will she could not bend, whom she could not cajole, whose mind was a closed book to her — a book which had lain by her hand for three years, which she had never had the curiosity to open!1906, Mary Cholmondeley, Prisoners: Fast Bound in Misery and Iron:
- Like the activities of British Railways Research Department, developing, testing and modifying diesel locomotives before their acceptance for service is another behind-the-scenes activity which is a closed book to most passengers and to many railwaymen.1962 April, R. K. Evans, “The Acceptance Testing of Diesel Locomotives”, in Modern Railways, page 266:
- Antonyms
- open book