What are the full words of pros and cons?

The full form of Pros and cons is pro et contra.

It means : for and against.

The term has been in use since the 16th century and is a shortening of a Latin phrase.

Pros are arguments which aim to promote the issue, while cons suggest points against it. Considering the pros and cons of an issue is a very useful way to weigh the issue thoughtfully and reach an informed decision.

Regards Subhransu Ghosh