Lucernal \Lu*cer"nal\, a. [L. lucerna a lamp.]

Of or pertaining to a lamp.

Lucernal microscope, a form of the microscope in which the object is illuminated by means of a lamp, and its image is thrown upon a plate of ground glass connected with the instrument, or on a screen independent of it.

Source: Webster's Revised Unabridged Dictionary (1913)