Source : Webster's Revised Unabridged Dictionary (1913)

Monoclinal \Mon`o*cli"nal\, a. [See {Monoclinic}.] (Geol.)
   Having one oblique inclination; -- applied to strata that dip
   in only one direction from the axis of elevation.

Source : WordNet®

monoclinal
     adj : of a geological structure in which all strata are inclined
           in the same direction