Word of the Day, November 13: ‘Lunatic’

Word of the Day: LUNATIC
Pronunciation: LOO-nuh-tik
UK /ˈluːnətɪk/
US /ˈluːnətɪk/

Meaning

Lunatic is a noun and an adjective commonly used to describe someone who behaves in an extremely foolish, reckless or irrational way. As a noun, it refers to a person whose behaviour seems wildly unreasonable. As an adjective, it describes an action, idea or situation that appears absurd or completely unreasonable.

Examples in everyday sentences

• Only a lunatic would drive at such a speed on a busy road.
• It was a lunatic idea to climb the mountain without proper equipment.
• My friends thought I was a lunatic for travelling alone without a fixed itinerary.

Origin and history

Lunatic comes from the Latin word lunaticus, meaning 'moon-struck', which is derived from luna, meaning 'moon'. It entered English through the Old French word lunatique during the late 13th century.

The word originated from an old belief that the changing phases of the moon could influence a person's mind and cause periods of unusual or disturbed behaviour. Similar beliefs existed in several ancient cultures, where the moon was associated with changes in human behaviour.

By the late 14th century, lunatic was also being used as a noun for a person believed to be affected by such conditions. Over time, its meaning expanded to include people considered foolish, irrational or reckless. The word lunacy, meaning madness or extreme foolishness, developed from it during the 16th century.

Although the belief connecting the moon to mental illness has no scientific basis, the word remains part of everyday English. 

Cultural significance and modern usage

Lunatic has appeared in literature, political commentary, films and everyday conversations for centuries. It is often used to express disbelief at someone's behaviour or to describe an action that seems dangerously unreasonable.

One familiar expression is lunatic fringe, which refers to an extreme or radical section of a larger group or movement. The expression was popularised by American President Theodore Roosevelt in 1913 when he used it to describe extreme elements within reform movements. 

The word also appears in phrases such as lunatic idea and lunatic behaviour, usually to emphasise how impractical or reckless something seems.

Interesting facts

The Latin word luna means moon. It is also the root of words such as lunar and lunation.

The belief that the moon influenced human behaviour is the reason behind the original meaning of lunatic.

The word lunacy first appeared in English during the 1540s.

Examples from literature

• “The lunatic, the lover, and the poet / Are of imagination all compact.” — A Midsummer Night's Dream, Act V, Scene I by William Shakespeare. 

Synonyms

• Maniac
• Madcap
• Madman
• Fool
• Eccentric

Antonyms

• Sane
• Sensible
• Rational