semiformal evening dress for men
"He put on his crisp white tuxedo to attend the gala, feeling instantly more confident in the black tie attire."
A tuxedo.
"He looked sharp in his black tux at the wedding."
A cuddly cartoon penguin, the official Linux mascot.
"The server logs are filled with Tux because everyone on our team loves sending him cute animated GIFs to celebrate successful deployments."