Is atheism a belief?

[Deesse23]

Do you believe everything people point out?  That's why you do research.  It someone tells you something, check it out for yourself.

A "dictionary" is an authority for defining terms. 

If you won't listen to the Merriam-Webster dictionary, then you surely aren't going to accept my definition for something.

Lets see how M-W dictionary defines dictionary then.  

1 : a reference source in print or electronic form containing words usually alphabetically arranged along with information about their forms, pronunciations, functions, etymologies, meanings, and syntactic and idiomatic uses

2 : a reference book listing alphabetically terms or names important to a particular subject or activity along with discussion of their meanings and applications

3 : a reference book listing alphabetically the words of one language and showing their meanings or translations in another language

4 : a computerized list (as of items of data or words) used for reference (as for information retrieval or word processing)

Where does M-W say that dictionaries define anything?

The fact that dictionaries only refer to current usage of words is pretty evident once you consider that dictionaries start including new words/terms or change the *definition* after they acknowledged the new word/term or changed usage already is applied in everyday used by society.
Nobody reads a dictionary to tell him on how to use a word (but Max maybe) but to inform himself about the current consensus of usage. Otoh the *i have an authoritative book* fallacy is pretty common amongst adherents of (abrahamic) religions.