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Harrow
Harrow [EBD]
(Heb. harits), a tribulum or sharp threshing sledge; a frame armed on the under side with rollers or sharp spikes (2 Sam. 12:31; 1 Chr. 20:3).
Heb. verb sadad, to harrow a field, break its clods (Job 39:10; Isa. 28:4; Hos. 10: 11). Its form is unknown. It may have resembled the instrument still in use in Egypt.
Harrow [NAVE]
HARROW, an agricultural implement used as an instrument of torture, 2 Sam. 12:31; 1 Chr. 20:3.HARROW [SMITH]
The word so rendered, (2 Samuel 12:31; 1 Chronicles 20:3) is probably a threshing-machine. The verb rendered "to harrow," (Job 39:10; Isaiah 28:24; Hosea 10:11) expresses apparently the breaking of the clods, and is so far analogous to our harrowing --but whether done by any such machine as we call a "harrow" is very doubtful.HARROW [ISBE]
HARROW - har'-o (sadhadh): Sadhadh occurs in 3 passages (Job 39:10; Isa 28:24; Hos 10:11). In the first 2 it is translated "harrow," in the last "break the clods." That this was a separate operation from plowing, and that it was performed with an instrument drawn by animals, seems certain. As to whether it corresponded to our modern harrowing is a question. The reasons for this uncertainty are: (1) the ancient Egyptians have left no records of its use; (2) at the present time, in those parts of Palestine and Syria where foreign methods have not been introduced, harrowing is not commonly known, although the writer has been told that in some districts the ground is leveled after plowing with the threshing-sledge or a log drawn by oxen. Cross-plowing is resorted to for breaking up the lumpy soil, especially where the ground has been baked during the long rainless summer. Lumps not reduced in this way are further broken up with a hoe or pick. Seed is always sown before plowing, so that harrowing to cover the seed is unnecessary. See AGRICULTURE. Figuratively used of affliction, discipline, etc. (Isa 28:24).James A. Patch
Also see definition of "Harrow" in Word Study