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, √-9, a + b √-
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.) An
imaginary expression or quantity.