Charles Ellicott Commentary Jeremiah 13:18

"Say thou unto the king and to the queen-mother, Humble yourselves, sit down; for your headtires are come down, even the crown of your glory." — Jeremiah 13:18 (ASV)

The queen. — Not the usual word, the Hebrew feminine of king, but literally “the great lady” (“ dominatrix ” Vulgate), the title of a queen-mother (in this case, probably, of Nehushta, the mother of Jehoiachin, 2 Kings 24:8), sharing the throne during her son’s minority. The same word is used of Maachah, the mother of Asa (1 Kings 15:13; 2 Kings 10:13; 2 Chronicles 15:16), and meets us again in Jeremiah 29:2.

Your principalities. — Literally, as in the margin, your head-tires, i.e., the diadems which were signs of kingly state. The word is used nowhere else, and may have been coined by the prophet or taken from the court vocabulary of the time.