Source : Webster's Revised Unabridged Dictionary (1913)

Delapse \De*lapse"\, v. i. [imp. & p. p. {Delapsed}; p. pr. &
   vb. n. {Delapsing}.] [L. delapsus, p. p. of delabi to fall
   down; de- + labi to fall or side.]
   To pass down by inheritance; to lapse. [Obs.]

         Which Anne derived alone the right, before all other,
         Of the delapsed crown from Philip.       --Drayton.