Meathead American informal noun slang
Used to describe a stupid or dull person
I don't believe that a meathead like him can win the chess tournament.
He didn't want to share a room with those 2 meatheads, so he changed his room.
Extremely stupid
Very stupid, or silly
To be extremely stupid; not to be alert
(n): a fool person,
(adj): stupid, foolish, silly
People often say that the term "meathead" comes from the classic 1970s television situation comedy "All In The Family," in which main character Archie Bunker (Carroll O'Connor) used the nickname to address his son-in-law, Michael Stivic (Rob Reiner), beginning with the premiere episode ("Meet the Bunkers") on January 12, 1971. However, the term first appeared in print in 1863.
If someone or something stands/sticks out like a sore thumb, they are so noticeable that the surrounding people and things notice them.
The dress codes of the wedding are blue and green, but Liza wore the red dress - she stuck out like a sore thumb.