noun
lunatic
LOO-nuh-tihk
noun
1
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."
adj
1
Crazy, reckless, or completely irrational.
"Only a lunatic would try to cross that motorway on foot."
"He came up with some lunatic scheme to double his savings overnight."
How to Use Lunatic
Learner’s notesIn plain EnglishSomeone or something completely crazy or irrational.
When to use it
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."
Common pairings
a lunatic idea
lunatic asylum (dated)
lunatic fringe
Word Forms
more lunatic comparative, lunatics plural, most lunatic superlative
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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.
Related Words
Rhymes for lunatic
static
aquatic
fanatic
hepatic
erratic
aromatic
ecstatic
operatic
dramatic
climatic
emphatic
Adriatic
See all rhymes for lunatic →