Meaning of the word fallacious in English

What does fallacious mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

fallacious

US /fəˈleɪ.ʃəs/
UK /fəˈleɪ.ʃəs/

Adjective

based on a mistaken belief

Example:
The argument was based on fallacious reasoning.
It's a common but fallacious assumption.