1)
What is the meaning of "Utzu"?
1.
Rashi: It is a command (make a counsel). Radak - the Shuruk under the Ayin is in place of a Cholem. It should have a Cholem, because the first letter of the root is omitted, like "Goshu Henah" (Yehoshua 3:9).
2)
Does this address a particular counsel?
1.
Radak: Yes - their counsel [to conquer] Yerushalayim.
2.
Malbim: Yes - how to sustain the conspiracy.