After reading a review that described this thesaurus as being written in a code of its own, virtually unintelligible, I felt compelled to provide some updated information. When I first received the thesaurus I found looking up words with the provided thematic system of classification somewhat daunting. The Historical Thesaurus of the OED uses a thematic system of classification and is organized into three major sections: I The external world; II The mental world; III The social world. From these broad catagories you can simply narrow down your search into more specific catagories. An example of this structure is 02 The mind ....02.02 Emotion....02.02.22 Love....02.02.22.04 Terms of endearment.... Overall, the Historical Thesaurus of the Oxford English Dictionary contains almost 800,000 meanings, organized into more than 236,000 categories and subcategories. The concept is fantastic and if you are having trouble coming up with a synonym the thematic system is very effective albeit somewhat slow.
It wasn't until several days into using the thesaurus that I stumbled into the second volume. The entire volume (all 2,109 pages of it) are dedicated to words with references to sections in volume 1 for their synonyms. Volume 1 is the Thesaurus itself, organized according to the semantic categories outlined above, while Volume 2 is an alphabetical Index listing the majority of the synonyms in Volume 1. You can approach the content of the Thesaurus in different ways: either by looking up a single lexical item in the Index and be directed to the appropriate section in the main Thesaurus, or by browsing by semantic category directly, and seeing words in their context of both historical development and the overall organization of meaning.
To get a flavor of the workings of the thesaurus and a sample page go to Oxford University Press web site (Sorry but Amazon will not let me insert the link, just think "OED", then search the site for historical thesaurus, then click on the link Read more about "the largest thesaurus in the world" link).
I was very hesitant to shell out $$$ for book I didn't know if I would like, but retrospectively I don't regret the purchase and have had a lot of fun with it. I also purchased the CD ROM version 4.0 of the dictionary Oxford English Dictionary, 2nd Edition, Version 4.0 (Windows & Mac) and have found it to be equally useful. I believe anyone who found this thesaurus to be an "Indecipherable Code" may not have explored Volume 2. Hope this review helps.
Also dasy-, daysy-, dasa-, dose-, dosa-, dossi-, doziberd(e, dosebeirde.
[The better form is prob. dasyberd = dazy-beard: see dazy a. inert, dull. Mätzner compares LG. dösbârt, and the same notion appears in Lowland Sc. dulbart, dulbert = dull-beard, dullard.]
A stupid fellow, dullard, simpleton.