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

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, [root]-9, a + b
[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.

© Webster 1913.

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

An imaginary expression or quantity.

© Webster 1913.