Word Study
anallagmatic
CIDE DICTIONARY
anallagmatic, a. [Gr. ; 'an priv. + a change.].
Not changed in form by inversion. [1913 Webster]
Anallagmatic curves, a class of curves of the fourth degree which have certain peculiar relations to circles; -- sometimes called bicircular quartics . -- Anallagmatic surfaces, a certain class of surfaces of the fourth degree.
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