imaginary

adjective

imag·​i·​nary i-ˈma-jə-ˌner-ē 

-ˌne-rē

1

a

: existing only in imagination : lacking factual reality

an imaginary friend

b

: formed or characterized imaginatively or arbitrarily

His canvases, chiefly imaginary, somber landscapes …

—Current Biography

2

: containing or relating to the imaginary unit

imaginary roots

imaginarily

i-ˌma-jə-ˈner-ə-lē 

adverb

imaginariness

i-ˈma-jə-ˌner-ē-nəs 

noun

Synonyms of imaginary

• fictitious
• fictional
• mythical
• imagined
• fantasied
• imaginal

Choose the Right Synonym for imaginary

imaginary, fanciful, visionary, fantastic, chimerical, quixotic mean unreal or unbelievable.

imaginary applies to something which is fictitious and purely the product of one's imagination.

an imaginary desert isle

fanciful suggests the free play of the imagination.

a teller of fanciful stories

visionary stresses impracticality or incapability of realization.

visionary schemes

fantastic implies incredibility or strangeness beyond belief.

a fantastic world inhabited by monsters

chimerical combines the implication of visionary and fantastic.

chimerical dreams of future progress

quixotic implies a devotion to romantic or chivalrous ideals unrestrained by ordinary prudence and common sense.

a quixotic crusade

Examples of imaginary in a Sentence

The two groups were separated by an imaginary line down the middle of the room.

an imaginary world of dragons and unicorns

Recent Examples on the Web

Near the end of the story, Gardner pledges to kill his imaginary son to spare him war’s toll, but backs out upon his wish to be transformed into a noble soldier. — Literary Hub, 10 Aug. 2026

The Argentinian prairie is adorned with imaginary houses, castles and theatres as the young girls construct spontaneous, invisible cities, stories and games in which Koberidze’s likewise unseen characters could live. — Manahil Tahira, Variety, 10 Aug. 2026

School functions, practices, appointments and sick days can seem quietly designed around an imaginary second adult. — Kristin Vance Richards, Forbes.com, 10 Aug. 2026

Blowing up an imaginary balloon, using a pinwheel or pretending to blow out birthday candles can make the practice feel less like a chore. — Samantha Agate, Fort Worth Star-Telegram, 10 Aug. 2026

Word History

Etymology

Middle English ymaginarie, borrowed from Latin imāginārius "unreal, fictitious (in law)," from imāgin-, imāgō "representation, semblance, image entry 1" + -ārius -ary entry 2

First Known Use

15th century, in the meaning defined at sense 1a

Phrases Containing imaginary

• imaginary number
• imaginary part
• imaginary unit
• pure imaginary

Rhymes for imaginary

• accretionary
• apothecary
• bicentenary
• certiorari
• concessionary
• concretionary
• confectionary
• confectionery
• constabulary
• contemporary
• deflationary
• depositary

Kids Definition

imaginary

adjective

imag·​i·​nary im-ˈaj-ə-ˌner-ē 

: existing only in imagination : not real

unicorns are imaginary

Medical Definition

imaginary

adjective

imag·​i·​nary im-ˈaj-ə-ˌner-ē 

: existing only in imagination : lacking factual reality

imaginary fears

an imaginary illness