Tag used to name people with Pokémon names/words in their URL on Tumblr. However, most of these people only consider pokemon url people with canon Pokémon names as their url; like Pikachu, Mew, Arceus, etc. Also about 60% of the people in that tag only use it to bash against canon pokemon url owners for thinking they're better than the rest.
"I just looked through all the pokemon urls. They’re all taken."
"Who cares about canon pokemon urls, i have gengars, pik4chu, and hydreigoon."
"All i want is a canon pokemon url like Arceus, Xerneas, Kyurem, Mewtwo or Jirachi."