fallacious
8 synonyms and 5 antonyms for fallacious, grouped by meaning and by how common each one is.
Adjective — Based on faulty reasoning or a mistaken belief, and therefore wrong.
Synonyms
Everyday swaps
Common words most readers know — safe in any writing.
Less common
Still standard English, but they carry more weight.
Rare, literary or technical
Precise, but they will stand out — check the sense before using one.
Synonyms by Meaning
1. adjective formal
Based on faulty reasoning or a mistaken belief, and therefore wrong.
“The argument that prices always fall in a recession is fallacious.”
Opposites
2. adjective formal
Likely to mislead someone, whether or not deliberately.
“The advert made fallacious claims about the product's health benefits.”
Opposites
How to use fallacious
The word patterns that sound natural to a native speaker.
Formal. Most at home in academic writing, philosophy, law and argument analysis; in everyday speech people usually just say wrong or misleading.
Etymology
From Latin fallax, fallac- 'deceitful', from fallere 'to deceive'. The same root gives English fail, fault and false.
Full origin of fallacious →Frequently asked questions
What is the difference between fallacious and false?
False simply means untrue, whereas fallacious means the reasoning used to reach a conclusion is defective. A fallacious argument can even reach a true conclusion by bad logic, and a false statement can be made without any argument at all.
What is the difference between fallacious and fallible?
Fallacious describes an argument or belief that is logically unsound. Fallible describes a person or system that is capable of making mistakes. People are fallible; their arguments may be fallacious.
Is fallacious the adjective of fallacy?
Yes. A fallacy is a flaw in reasoning, and fallacious is the adjective describing anything that contains one, such as a fallacious claim or a fallacious line of argument.