The word Encyclopaedia (Encyclopedia) was first defined in Sir Thomas Elyot's LatinDictionary (1538) as 'that lernynge whiche comprehendeth all lyberall science and studies.' It was first used as the title of a book by Johann Heinrich Alsted in 1608, by which time it had acquired its modern meaning of a book covering every branch of humanknowledge. The term is also, however, applied to a work confined to some particular branch of knowledge. The distinction between an encyclopaedia and a dictionary is that the former explains subjects and the latter explains words. And the distinction between a glossary and an encyclopaedia is one of depth, the glossary being much more concise and often restricted to a particular subject, for example horticulture. Research Encyclopaedia