This is the 4227th most frequent Catalan word.
estúpid
"Estúpid" means "stupid" in English.
In this sentence, 'estúpid' is used in an imperative context to admonish or advise a person to avoid being unreasonable or making errors in understanding.
No siguis estúpid, entén el que dic.
Don't be stupid, understand what I am saying.
Here, 'estúpid' is applied descriptively to characterize a specific entity (the comment) as lacking relevance or thoughtfulness.
Aquest comentari és estúpid i fora de lloc.
This comment is stupid and out of place.
In this scenario, 'estúpid' is used reflectively to express an opinion about the appearance or perceived rationality of an idea before it proved effective.