Il*lapse" (?), v. i. [imp. & p. p. Illapsed (?); p. pr. & vb. n. Illapsing.] [L. illapsus, p. p. of illabi; pref. il- in + labi to fall, slide.] To fall or glide; to pass; -- usually followed by into. Cheyne.

Il*lapse", n. [L. illapsus. See Illapse, v. i.] A gliding in; an immisson or entrance of one thing into another; also, a sudden descent or attack. Akenside.

They sit silent . . . waiting for an illapse of the spirit.