IPA: /ɪnˌsaɪkləˈpiːdiə/
KK: /ɪnˌsaɪkləˈpiːdiə/
A book or set of books that provides detailed information on many subjects, usually arranged in alphabetical order.
I looked up the history of ancient Egypt in the encyclopaedia.
Encyclopaedia → It is formed from "en-" (meaning in or within), "kyklos" (meaning circle), and "paideia" (meaning education or upbringing). The word combines to describe a comprehensive work that encompasses all areas of knowledge, as if encircling the entirety of education.
Imagine a circle of knowledge ('kyklos') that contains all forms of education ('paideia') — that's what an encyclopaedia is, a book that holds a wide range of information.