Arch. [f. Gr. λύχνο-ς lamp + -σκόπος -SCOPE.] A name given to the LOW SIDE WINDOW on the supposition that its purpose was to allow lepers to see the altar lights.
1843. Ecclesiologist, II. 71. A paper on the windows called Lychnoscopes, in the fourth edition of the [Cambridge Camden] Societys Hints on the Practical Study of Ecclesiastical Antiquities. Ibid. (1846), V. 165. Lychnoscopes are nothing else than the symbolical representation of the Wound in the Saviours Side.
1848. B. Webb, Continental Ecclesiol., 57. The dwarf-wall is pierced by a broad fenestrella with a trefoliated head opening through into the aisle. This in England would be called a lychnoscope.
1866. Parker, Gloss. Terms Goth. Archit.
Hence Lychnoscopic a.
1849. Ecclesiologist, IX. 314. Behind it is a small chamber with a kind of lychnoscopic window. Ibid. (1852), XIII. 216.