What’s a prefix meaning 12? Even if you know the answer is “dodeca-” you will still find the Letts Maths Dictionary 11-14 useful and attractive to use. It covers the entire vocabulary from Years 6 to 9, and offers much more than mere definitions, though these are carefully done in accessible language. You also get symbols where appropriate, examples of the word in use, related terms (for example, ordinal number” leads to “cardinal number”) and background information. Where pictures help - as with Mobius strips - they have also been included. Letts Maths Dictionary 11-14 by Gillian Rich costs pound;5 from booksellers. Free resources are also available by visiting www.letts-education.comdictionariesmaths