非諧
Anharmonic \An`har*mon"ic\, a. [F. anharmonique, fr. Gr. 'an
priv. + ? harmonic.] (Math.)
Not harmonic.
{The anharmonic function} or {ratio} of four points abcd on a
straight line is the quantity (ac/ad):(bc/bd), where the
segments are to be regarded as plus or minus, according to
the order of the letters.