Browsing through a dictionary – almost any dictionary – has long been a pleasure for me: words open up worlds, and thus a dictionary allows the discovery of words, and therefore worlds, that you may previously have never known existed – or only in the haziest sense of ‘here lies dragons’ in an ancient atlas.

The same is true for the recently published ‘Illustrated Dictionary of Parasitology in the Post-genomic Era’. With two well-known and respected parasitologists, Hany M. Elsheikha and Edward L. Jarroll, as guides, it is a pure pleasure to explore and discover anew, or in greater depth, sections of the parasitology cosmos. The definitions provided for each entry are clear and unambiguous, with a deceptive simplicity that is easy to read, but difficult to write. The authors cover all aspects of parasitology, focussing, as the book's title indicates, not only on traditional parasitology concepts, but also on cutting-edge techniques in molecular parasitology, including subjects such as immunology, biochemistry and biotechnology. I find it hard to believe that even the most experienced parasitologist will have a grasp of all the terminologies covered so clearly and concisely here, and will not find something new and interesting.

Nevertheless, the price demanded for a pleasant browse is high – and these days a dictionary really is probably largely for browsing, rather than consulting, as people tend to turn to Google for checking facts or terminology.

The illustrations are a mystery – they seem to be scattered somewhat randomly throughout; many double-spreads have two, and between ‘bots’ and ‘bursa of Fabricius’ there are four, but then from bursitis there is a total absence until cestode. None are labelled, and although some are illustrative of the preceding entry, for others it is below. In addition, for some the precise intention of the illustration is unclear.

Also, certain parasite entries are included down to the species level, some only to the genus level, some as a disease but without the parasite name as a separate entry, some with disease and species-level parasite as separate entries, some a mixture, and some, notably Giardia, not entered at all. It is always difficult to decide what to exclude and include, but the logic here is hard to follow. Giardia (a parasite on which the late Professor Jarroll's expertise is legendary) is one of the most common intestinal protozoans in humans and animals worldwide, so its absence is inexplicable.

Consequently, the pleasurable browsing of familiar and new concepts is reduced to identifying lacunae. Errors become major aggravations – one does, after all, expect a dictionary to have near-perfect spelling.

Despite these omissions, errors, and a high price, this book could be a nice treat for a research group or a library.