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Fausset's Bible Dictionary [1]

 Jeremiah 36:26;  Jeremiah 38:6. Jehoiakim at this time (the fifth year of his reign) had no grown up son. Jeconiah his successor was then but eleven ( 2 Kings 23:36; compare  2 Kings 24:8). We must not then, with Smith's Bible Dictionary, translated "the king," but as a proper name, Hammelech, father of Jerahmeel and Malchiah.

Hastings' Dictionary of the Bible [2]

Hammelech occurs as a proper name in AV [Note: Authorized Version.] and RVm [Note: Revised Version margin.] of   Jeremiah 36:26;   Jeremiah 38:6 , but there is little doubt that the rendering ought to be ‘the king,’ as in RV [Note: Revised Version.] and AVm [Note: Authorized Version margin.] .

Morrish Bible Dictionary [3]

Father of Jerahmeel and Malchiah, as in the A.V. The word is considered by some not to be a proper name, but to signify 'the king,' reading 'Jerahmeel, the king's son,' and 'Malchiah, the king's son,'  Jeremiah 36:26;  Jeremiah 38:6; as in the margin and the R.V.

Smith's Bible Dictionary [4]

Ham'melech. Literally, "The King". Unnecessarily rendered, in the Authorized Version, as a proper name.  Jeremiah 36:26;  Jeremiah 38:6.

Holman Bible Dictionary [5]

 Jeremiah 36:26 Jeremiah 38:6

Easton's Bible Dictionary [6]

 Jeremiah 36:26

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [7]

(Heb. ham-Me'lek, הִמֶּלֶךְ ', which is merely מֶלֶךְ ', me'lek, king, with the article prefixed; Sept. translates Βασιλεύς , Vulg. Amelech), the father of Jerahmeel, which latter was one of those commanded by Jehoiakim to arrest Jeremiah and Baruch ( Jeremiah 36:26). B.C. ante 605. It is doubtful whether this was the same with the Hammelech, father of Malchiah, into whose dungeon Jeremiah was afterwards cast ( Jeremiah 38:6). B.C. ante 589.'Others, however, regard the word in both cases as an appellative, referring in the first passage to Jehoiakim, and in the latter to Zedekiah. (See Hammoleketh).

International Standard Bible Encyclopedia [8]

ham´ē̇ - lek ( המּלך , ha - melekh , "the king"): Wrongly translated as a proper name in the King James Version. It should be rendered "the king," as in the American Standard Revised Version ( Jeremiah 36:26;  Jeremiah 38:6 ).