When you're a graduate people expect you to use a vocabulary which is wider than a school-leaver's. To expand your vocabulary:

• Choose a large dictionary rather than one which is ‘compact' or ‘concise'. You want one which is big enough to define words clearly and helpfully (around 1,500 pages is a good size).
• Avoid dictionaries which send you round in circles by just giving synonyms. A pocket dictionary might suggest: ‘impetuous = rash'.
• A more comprehensive dictionary will tell you that impetuous means ‘rushing with force and violence', while another gives ‘liable to act without consideration', and add to your understanding by giving the derivation ‘14th century, from late Latin impetuous = violent'.
• It will tell you that rash means ‘acting without due consideration or thought', and is derived from Old High German rasc = hurried.
• So underlying these two similar words is the difference between violence and hurrying.
• There are over 600,000 words in the Oxford English Dictionary; most of them have different meanings, (only a small proportion are synonyms).
• Avoid dictionaries which send you round in circles by using very complicated language to define the term you're looking up, leaving you struggling to understand half a dozen new words.
• Keep your dictionary at hand when you're studying. Look up unfamiliar words and work to understand what they mean.
• Improve your vocabulary by reading widely.
• If you haven't got your dictionary with you, note down words which you don't understand and look them up later.

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