From BiblePortal Wikipedia

Morrish Bible Dictionary [1]

This refers to the river Nile. In  Joshua 13:3 it is "Sihor which is before Egypt." In   Isaiah 23:3 the produce of the harvest of Egypt was brought to the sea by the river, and from thence was fetched by the Syrian merchants. In   Jeremiah 2:18 Israel is warned against seeking the waters of the Nile; that is, trusting in Egypt instead of in God: cf.   Jeremiah 2:36 . In  1 Chronicles 13:5 it is written Shihor as the south-west boundary of Palestine. Some consider that   Joshua 13:3 and   1 Chronicles 13:5 refer to the Wady el Arish, which was also called 'the river of Egypt.'

Smith's Bible Dictionary [2]

Si'hor. (Dark). Accurately, Shi'hor , once, The Shihor , or Shihor of Egypt , when unqualified, a name of the Nile. It is held to signify "The Black" or "Turbid". In Jeremiah, the identity of Shihor with the Nile seems distinctly stated.  Jeremiah 2:18. The stream mentioned in  1 Chronicles 13:5 is possibly that of the Wadi L' Areesh .

American Tract Society Bible Dictionary [3]

Black or turbid, the Nile. In  Isaiah 23:3 and   Jeremiah 2:18 , this name must necessarily be understood of the Nile. In  Joshua 13:3;  1 Chronicles 13:5 , some have understood it of the little river between Egypt and Judah.

Easton's Bible Dictionary [4]

 Isaiah 23:3 Jeremiah 2:18 Joshua 13:3  1 Chronicles 13:5

Holman Bible Dictionary [5]


Fausset's Bible Dictionary [6]

(See Shihor .)

Kitto's Popular Cyclopedia of Biblial Literature [7]

Si´hor, more properly Shichor, the Hebrew proper name for the Nile . The word means 'black;' and a corresponding name or epithet was by the Greeks applied to the same river on account of the black slime left after the subsidence of the inundation.