Meaning
primarily signifies "speech, conversation." The first syllable comes from a root mu--, signifying "to close, keep secret, be dumb;" whence, muo, "to close" (eyes, mouth) and musterion, "a secret, a mystery;" hence, "a story, narrative, fable, fiction" (Eng., "myth"). The word is used of gnostic errors and of Jewish and profane fables and genealogies, in 1Ti 1:4, 1Ti 4:7, 2Ti 4:4, Tit 1:14; of fiction, in 2Pe 1:16.
Muthos is to be contrasted with aletheia, "truth," and with logos, "a story, a narrative purporting to set forth facts," e.g., Mat 28:15, a "saying" (i.e., an account, story, in which actually there is a falsification of facts); Luk 5:15, RV, "report."