lunatic
12 synonyms and 1 antonym for lunatic, grouped by meaning and by how common each one is.
Noun — A person regarded as insane or wildly irrational (now considered old-fashioned and offensive as a clinical term).
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. noun
A person regarded as insane or wildly irrational (now considered old-fashioned and offensive as a clinical term).
“The old asylum was once, insensitively, referred to as a home for lunatics.”
2. adj
Crazy, reckless, or completely irrational.
“Only a lunatic would try to cross that motorway on foot.”
Opposites
How to use lunatic
The word patterns that sound natural to a native speaker.
As a label for a person with mental illness, this word is now considered offensive and dated; it survives mainly in the looser sense of "reckless" or "absurd," as in "lunatic idea."
Etymology
From Old French lunatique, from Late Latin lunaticus ("moonstruck"), from Latin luna ("moon") — reflecting the old superstition that changes in the moon triggered fits of madness.
Full origin of lunatic →