The noun conviction means a strong belief or a strong feeling of being certain about something. The noun conviction also means the case of officially being found to be guilty of a particular crime.

Synonyms are confidence, faith, feeling, or principle.

The word origins from Late Latin (mid 15th century) convictionem meaning “proof, refutation”, noun of action from past-participle stem of convincere meaning “to overcome decisively”. It comes from com-, here probably an intensive prefix (see com-), plus vincere meaning “to conquer”.

There was a conviction for slavery.

His conviction was clearly seen on his face.

Ronald’s statement lacked conviction.