This is a person fascinated with inserting the weights from cuckoo clocks up their cloacus because they like the way it feels.
The only thing that makes a German logger happier than entering a cuckoo clock store is exiting a cuckoo clock store.
Someone who logs a geocache find, without having actually visited the geocache. Quite often getting a fellow geocacher to sign their name in the logbook, while they are elsewhere.
They may have found a lot of geocaches, but everyone knows they are an armchair logger.
When you gotta take a big shit, and you drop it all in one steamy log, rather than many shits. Its glorious and sought after by many cultures. Some say it's where the term "holy shit" derives from. A one-logger must be chosen by God, and cannot be artificially induced, thus banning the faux-logger.
ex 1)
Guy1: hey man, i just dropped a one-logger!
Guy2: HOLY SHIT dude no way, u snap any pics?
Guy1: OFC, wanna see?
Guy2: Ive never seen anything so glorious.. what was it like..
ex2) the tweet:
Yo twitter, i just dropped a one-logger. #YOLO