As though someone or oneself is better or more important than others. Various slang and vulgar synonyms for "backside" are often substituted. (Note: If thought about oneself, it means that they are arrogant, conceited, or self-absorbed. If someone thinks this of another person, it means that they love or admire that person to such a degree as to be blinded to any of their potential faults.) Samantha has such an ego and acts as if the sun shines out her backside. He's absolutely head-over-heels in love with Mary. Even though I find her a bit irritating, to him it's as if the sun shines out her backside.