It occurred to me today that I may talk about bluetooth, meaning the technology in general, or a bluetooth device, meaning an instance of that device that uses bluetooth...but also "a bluetooth" or "my bluetooth" or "your bluetooth," which to me implicitly means a bluetooth headset. Usually, but not necessarily exclusively, a monaural one.

And when I realized that, I felt old. And until I realized that made me feel old, it had not occurred to me that it feels to me like the era of "Who is he talking to? Oh, he's got his bluetooth in" was essentially the aughts. Nowadays, it seems likely that either it'll be so commonplace as not to warrant notice, or someone will be holding their magic rectangle up (for some reason, usually flat and on speakerphone) so that it's obvious why they're talking, or the term that comes to mind will be earbud(s) or airpods. That was also when I realized I no longer think "earbuds" and wonder "wired or wireless?" but rather expect wired to be specified.

Personally I don't like either in-canal models or a secure enough in-ear fit not to need a hook, so I still use...my bluetooth.