conviction n.

word-forming element usually meaning "with, together," from Latin com, archaic form of classical Latin cum "together, together with, in combination," from PIE *kom- "beside, near, by, with" (compare Old English ge-, German ge-). The prefix in Latin sometimes was used as an intensive.

Before vowels and aspirates, it is reduced to co-; before -g-, it is assimilated to cog- or con-; before -l-, assimilated to col-; before -r-, assimilated to cor-; before -c-, -d-, -j-, -n-, -q-, -s-, -t-, and -v-, it is assimilated to con-, which was so frequent that it often was used as the normal form.

Proto-Indo-European root meaning "to fight, conquer."

It forms all or part of: convict; convince; evict; evince; invictus; invincible; Ordovician; province; vanquish; victor; victory; Vincent; vincible.

It is the hypothetical source of/evidence for its existence is provided by: Latin victor "a conqueror," vincere "to conquer, overcome, defeat;" Lithuanian apveikiu, apveikti "to subdue, overcome;" Old Church Slavonic veku "strength, power, age;" Old Norse vigr "able in battle," Old English wigan "fight;" Welsh gwych "brave, energetic," Old Irish fichim "I fight," second element in Celtic Ordovices "those who fight with hammers."

"those ideas which one believes to be true," 1830, plural of conviction.