Chambers Dictionary -

The Chambers Dictionary covers the latest words and meanings to enter the English language but also takes delight in preserving many rare, historical and dialect words that are omitted from other dictionaries.

Thus it offers a uniquely rich coverage of English vocabulary from Shakespeare to the present day.

This dictionary has more words and definitions than any other single-volume English dictionary; 

accurate, clear and, on occasion, characteristically witty definitions; 

over 500 new words and meanings covering recent developments in technology, culture and slang; 

easy-to-follow pronunciation guidance; 

scholarly explanations of word origins; 

and extensive appendices of foreign phrases, first names, scientific information, and conversion tables.