someone who will surely do something; something that will surely happen

to make certain of or to guarantee something

according to facts instead of opinions

in a definite and clear manner due to being based on facts instead of ideas or guesses

a belief or opinion that is very strong

having a strong belief in something or being certain about it

to put trust in something or someone

to check the accuracy or validity of something by using alternative sources or methods

‌an act of determining the accuracy or credibility of something by comparing it with various sources

in a way that is certain and beyond any doubt

certainly happening and unlikely to change

someone who is sure to do something or something that is sure to happen or one is certain about

being convinced that everything one believes in is true and others are wrong

in a critical and arrogant manner therefore refusing to consider other's opinions

to make sure that something will happen

something that is assumed to be true or already decided upon before any evidence or arguments are presented

to understand something completely and clearly

to make sure that something will occur

something that makes certain of a given result

a person who officially makes a promise or gives assurance to be accountable for someone or the occurrence of something

to assume without question that something is true