What is Know-it-all Idiot?
1.
Any person who obnoxiously acts like they know a lot on a given subject (as by refusing to accept advice or information from others, bragging to knowledge, trying to correct others, etc.) usually while there are also subtle or blatant signals that this person doesn't know as much as they're acting like they do; pretensions to knowledge
"Even though I'm only fifteen and I've never held a job before I want you to listen to me carefully; on your interview, if you're not sitting cross legged, they won't hire you. If you don't nod, they won't hire you. Employers hate when you don't wear a tie. Companies these days aren't into what's on your application. Employers these days are real into the whole look aspect of it all. Take it from me," said my know-it-all idiot son before I handed him his schoolbag and replied, "Shut up and go to school, dear!"
A know-it-all idiot, Amanda claimed she didn't need to go through training before she started at her new job as a doctor. Ultimately, she ended up killing one of her patients by using the equpment wrong and she was thrown in jail.
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