(door, side) post

Boyd’s Bible Dictionary:

(placed). Runners, messengers, on foot, on horses, or on dromedaries (Esther 8:10-14; Job 9:25; Jer. 51:31).

Concise Bible Dictionary:

The dispatch of letters with speed was of early date. Job said, “Now my days are swifter than a post” (Job 9:25). When Hezekiah proclaimed a Passover for all Israel he sent letters of invitation by “runners” from city to city (2 Chron. 30:6,10). The posts sent with the decree from Shushan the palace went on horses, mules, camels, and young dromedaries, “being hastened and pressed on by the king’s commandment” (Esther 3:13,15; Esther 8:10,14). In the prophecy of God’s judgments on Babylon it is said that the news should be carried to the king by one post running to meet another (Jer. 51:31). By dividing large districts into small departments with a post-house in each, in which “runners” and animals were always kept ready, dispatches could quickly be dispersed in various directions.

Strong’s Dictionary of Hebrew Words:

Transliteration:
mzuwzah
Phonic:
mez-oo-zaw’
Meaning:
or mzuzah {mez-oo-zaw'}; from the same as 2123; a door-post (as prominent)
KJV Usage:
(door, side) post