This is the 86th most frequent Portuguese word.
disso
"Disso" means "of that" or "about that" in English.
In this sentence, 'disso' stands in for an idea or topic mentioned earlier.
Não podemos nos esquecer disso.
We must not forget about this.
'Disso' here specifies awareness regarding information previously discussed or implied through the context.
Ele está ciente disso devido à reunião.
He is aware of this due to the meeting.
Here, 'disso' refers back to 'aquilo' and conveys a negative sentiment towards it.