Verb
1. make certain of;
"This nest egg will ensure a nice retirement for us""Preparation will guarantee success!"2. inform positively and with certainty and confidence;
"I tell you that man is a crook!"3. assure somebody of the truth of something with the intention of giving the listener confidence;
"I assured him that traveling to Cambodia was safe"4. be careful or certain to do something; make certain of something;
"He verified that the valves were closed""See that the curtains are closed""control the quality of the product"5. cause to feel sure; give reassurance to;
"The airline tried to reassure the customers that the planes were safe"6. make a promise or commitment