IMAGINARY

fanciful, imaginary, notional

(adjective) not based on fact; existing only in the imagination; “the falsehood about some fanciful secret treaties”- F.D.Roosevelt; “a small child’s imaginary friends”; “to create a notional world for oneself”

Source: WordNet® 3.1

Etymology

Adjective

imaginary (comparative more imaginary, superlative most imaginary)

Existing only in the imagination.

(mathematics, of a number) Having no real part; that part of a complex number which is a multiple of the square root of -1.

Synonyms

• (existing only in the imagination): all in one's head

Noun

imaginary (plural imaginaries)

Imagination; fancy. [from 16th c.]

(mathematics) An imaginary quantity. [from 18th c.]

(sociology) The set of values, institutions, laws, and symbols common to a particular social group and the corresponding society through which people imagine their social whole.

Source: Wiktionary

Im*ag"i*na*ry, a. Etym: [L. imaginarius: cf. F. imaginaire.]

Definition: Existing only in imagination or fancy; not real; fancied; visionary; ideal. Wilt thou add to all the griefs I suffer Imaginary ills and fancied tortures Addison. Imaginary calculus See under Calculus.

– Imaginary expression or quantity (Alg.), an algebraic expression which involves the impossible operation of taking the square root of a negative quantity; as, sq. root-9, a + b sq. root-1.

– Imaginary points, lines, surfaces, etc. (Geom.), points, lines, surfaces, etc., imagined to exist, although by reason of certain changes of a figure they have in fact ceased to have a real existence.

Syn.

– Ideal; fanciful; chimerical; visionary; fancied; unreal; illusive.

Im*ag"i*na*ry, n. (Alg.)

Definition: An imaginary expression or quantity.

Source: Webster’s Unabridged Dictionary 1913 Edition