Millo

(Heb. always with the article, "the" Millo). (1.) Probably the
Canaanite name of some fortification, consisting of walls filled
in with earth and stones, which protected Jerusalem on the north
as its outermost defence. It is always rendered Akra i.e., "the
citadel", in the LXX. It was already existing when David
conquered Jerusalem (2 Sam. 5:9). He extended it to the right
and left, thus completing the defence of the city. It was
rebuilt by Solomon (1 Kings 9:15, 24; 11:27) and repaired by
Hezekiah (2 Chr. 32:5).

(2.) In Judg. 9:6, 20 it is the name of a rampart in Shechem,
probably the "tower of Shechem" (9:46, 49).