When something is just so right that only one word can explain it. Only one word is relevant enough to highlight the relevance of the situation.
Billy: Hey pass me that ruler why don't you?
Ruth: Why should I do that? Are you going to measure that water tower?
Billy: That's totally unrelevant!
Ruth: It's pronounced irrelevant.
Billy: That's so relevant of you.
An organization of like minded individuals celebrating the art and sophistication of a well groomed mustache. A soul patch is an accessory and not considered part of a traditional mustache. Wearers are not welcome.
The APD sport the most ridiculous mustaches. Yeah, obviously not a single member of the Relevant Gentleman's Society among them.
Performing arguably "useful" searches in a store or on the internet when in fact you're just wasting time and goofing off.
Instead of scouring the bookstore or internet for assistance with his calculus homework, Steve spent untold hours engaged in relevant procrastination researching netbook computers "for his mom".
While our lifespan is the number of years we will live, our healthspan is the number of healthy years we will have and our sexspan is is the number of years we will continue to be healthy enough to continue having an active sex life.
A lighthearted reaction upon receiving disappointing news of some sort. Usually something that isn't a particularly a big deal, esp. when it primarily affects someone else - sort of a mild schadenfreude. Sometimes doubled or tripled, and possibly said in a sing-songy voice for added comedic effect to imitate a muted trumpet, which is how the meme originated.