[1] : The Collaborative International Dictionary of English v.0.48

imaginary \imag"inary\, a. l. imaginarius: cf. f.
   imaginaire.
   existing only in imagination or fancy; not real; fancied;
   visionary; ideal.
   1913 webster

         wilt thou add to all the griefs i suffer
         imaginary ills and fancied tortures?     --addison.
   1913 webster

   imaginary calculus see under calculus.

   imaginary expression or imaginary 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.
        1913 webster
see also:
imaginary calculus calculus imaginary expression imaginary quantity imaginary points lines 
surfaces 

Surfaces >> S Words
Surfaces, definition of term: Surfaces
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