An encyclopedia is a book or set of books in which facts about many different subjects or about one particular subject are arranged for reference, usually in alphabetical order.
英漢詞典釋義
n.
百科全書; (某一學科的)專科全書
I bought the encyclopedia on a whim.我憑一時的興致買了這本百科全書。
英英詞典釋義
Noun
1. a reference work (often in several volumes) containing articles on various topics (often arranged in alphabetical order) dealing with the entire range of human knowledge or with some particular specialty