Gaboso
When you see one dumb thing about someone and decide the whole group is as stupid as that one thing. Like you saw one guy wearing socks with sandals and now you think everyone in his class is a total moron.
My cousin saw a guy eating a whole pizza in one bite and now he thinks all Italians are fat.
I saw one kid draw a stick figure and now I think the whole art club is a joke.
My teacher saw one student fail and now she thinks the whole class is a bunch of losers.