Noun

(uncountable) The property of being sure, certainty.

:His sureness was born of having looked it up in a reputable reference book.

(uncountable) The property of being sure, deft, confident of ability.

:The surgeon's sureness was the result of long study in school and long practice in the operating room, never did he hesitate and never was there a mis-move.

(countable, rare) The result or product of being sure.

Noun

(en noun)

Mental acceptance of a claim as likely true.

*{{quote-magazine, date=2013-12-06, author=(George Monbiot)

, volume=189, issue=26, page=48, magazine=(The Guardian Weekly) , title= Why I'm eating my words on veganism – again , passage=The belief that there is no conflict between [livestock] farming and arable production also seems to be unfounded: by preventing the growth of trees and other deep vegetation in the hills and by compacting the soil, grazing animals cause a cycle of flash floods and drought, sporadically drowning good land downstream and reducing the supply of irrigation water.}}

Faith or trust in the reality of something; often based upon one's own reasoning, trust in a claim, desire of actuality, and/or evidence considered.

(countable) Something believed.

(uncountable) The quality or state of believing.

(uncountable) Religious faith.

(in the plural) One's religious or moral convictions.