Define Dslr Meaning

Digital Single Lens Reflex camera -- a digital camera that uses mirrors and a pentaprisim (or pentamirror) so that the optical viewfinder looks out through the camera lens. DSLRs are characterized by having interchangeable lenses and generally more professional features than point-and-shoot cameras, such as better autofocus, less noisy images in low light, and faster frame rates.

When inexperienced photographers have a professional camera but don't know how to use it properly, thus resulting in out-of-focus, blurry, or aesthetically displeasing photos.

The photographer of the friend circle. He is always seen moving around with a dslr camera hanging from his neck.
Sometimes it is just for showing off.
The term is often used sarcastically, to refer to guys, who become this type of wannabe photographers, just to be close with girls who are selfie queen.