Easton's Bible Dictionary: M. G. Easton, M.A., D.D.
Properly the absence of all colour. In Pr. 7:9 the Hebrew word means, as in the margin of the Revised Version, "the pupil of the eye." It is translated "apple" of the eye in Dt. 32:10; Ps. 17:8; Pr. 7:2. It is a different word which is rendered "black" in Lev. 13:31, 37; Song 1:5, 5:11; and Zech. 6:2, 6. It is uncertain what the "black marble" of Esther 1:6 was which formed a part of the mosaic pavement.