From Longman Dictionary of Contemporary Englishnotebooknote‧book /ˈnəʊtbʊk $ ˈnoʊt-/ ●●● S3 noun [countable] 1 
DTCNa book made of plain paper on which you can write notes2 TD (also notebook computer) a small computer that you can carry with you → laptop
DTCNa book made of plain paper on which you can write notes2 TD (also notebook computer) a small computer that you can carry with you → laptopExamples from the Corpus
notebook• His companion was thin and nervy and carried a notebook.• As they searched, they wrote down in a notebook details of all the things they found.• A teacher had assigned the class to make a composition by taping personal objects into a notebook.• Viol pulled out a notebook and a biro.• He closed his notebook, stood up, made a motion at Vinny Pearson.• In the main compartment were two very old-looking notebooks bound in calfskin; nothing else.• Imagine having your own self-contained knowledge manipulator in a portable package the size and shape of an ordinary notebook.• Couldn't have picked up the pen and opened the notebook and faced the blank page.From Longman Business Dictionarynotebooknote‧book /ˈnəʊtbʊkˈnoʊt-/ noun [countable] COMPUTING a small personal computer which is easy to carry somewhere with youIt says it is offering the industry’s most advanced notebooks at competitive prices.These screens add about $2,000 to the price of a notebook computer. → compare laptop 