1. to make safe (as from risks or against overthrow) : insure
2. to give confidence to
3. to make sure or certain : convince
4. to inform positively
5. to make certain the coming or attainment of : guarantee
2 : and hereby we know that we are of the truth, and shall assure our hearts — 1 John 3:19

3 : He glanced back to assure himself that no onw was following.

4 : I assure you that we can do it.

5 : The man worked hard to assure accuracy.
by saugirl January 23, 2010
How "sure" you are on a particular subject
My assurity is low on how successful rocket boots will be.
by William M. Buttlicker February 7, 2009
what was that againg? uhh sure-ance?
by Yeap August 3, 2004
confidence in yourself and your abilities
But for girls who lack that armor of self-assurance, the insecurity I felt after reading Seventeen must have been even more unbearable.
by Weeheh October 14, 2014
A phrase that is utilized to express positiveness, a guarantee, or just general "knowing" of a person, subject, or event.
Jake: "Was the party at TJ's really as cool as everyone said it was?"
Dre: "Hell yeah man. Everyone was having a good time."
Jake: "Man, for real? And I missed it?!"
Dre: "Rest Assured Jake. You missed more than you'll ever know..."
by stunna3098 October 10, 2011
Normally heard in the context of `mutually assured destruction`; when something is mutually assured, it is guaranteed to happen to both parties involved. This phrase is normally linked to discussions involving nuclear weapons, where `mutually assured destruction` means that we are all guaranteed to die.
Hindsight is always 20-20
But looking back it's still a bit fuzzy
Speak of mutually assured destruction?
Nice story...tell it to Reader's Digest!

- Megadeth, _Sweating Bullets_
by Wingchild September 13, 2003