Heb. matstsab, a station; a place where one stands (1 Samuel 14:12); a military or fortified post (1 Samuel 13:23; 14:1,4,6, etc.).
Heb. netsib, a prefect, superintendent; hence a military post (1 Samuel 10:5; 13:3,4; 2Sam 8:6). This word has also been explained to denote a pillar set up to mark the Philistine conquest, or an officer appointed to collect taxes; but the idea of a military post seems to be the correct one.
Heb. matstsebah, properly a monumental column; improperly rendered pl. "garrisons" in Ezekiel 26:11; correctly in Revised Version "pillars," marg. "obelisks," probably an idolatrous image.
These dictionary topics are from M.G. Easton M.A., D.D., Illustrated Bible Dictionary, Third Edition, published by Thomas Nelson, 1897. Public Domain, copy freely.
Easton, Matthew George. "Entry for 'Garrison'". "Easton's Bible Dictionary".