Strong's #1598: ganan (pronounced gaw-nan')
 a primitive root; to hedge about, i.e. (generally) protect:--defend.
Brown-Driver-Briggs Hebrew Lexicon:
 ּ 
  gânan 
 
 1) to defend, cover, surround
 
 1a) (Qal) to defend
 1b) (Hiphil) to defend
 
  Part of Speech: verb
Relation: a primitive root
Usage:
This word is used 8 times:
2 Kings 19:34: " For I will defend this city, to save it, for mine own sake, and for my servant David's"
2 Kings 20:6: "city out of the hand of the king of Assyria;  and I will defend this"
Isaiah 31:5: "so will the LORD of hosts  defend Jerusalem; defending also he will deliver"
Isaiah 31:5: "of hosts defend Jerusalem;  defending also he will deliver it; and passing over he will preserve"
Isaiah 37:35: " For I will defend this city to save it for mine own sake, and for my servant David's"
Isaiah 38:6: "out of the hand of the king of Assyria:  and I will defend this city."
Zechariah 9:15: "of hosts  shall defend them; and they shall devour, and subdue with slingstones;"
Zechariah 12:8: "day shall the LORD  defend the inhabitants of Jerusalem; and he that is feeble"