It is rare to come across one, but recently we were all proven that it exists. Canonically hot is when a character is officially hot, as told by the creator or in other official sources that have not been corrected statements later on. When this is confirmed, it is likely
true in real life as well.
The particular reason that this
definition was created was because Nintendo of America president
Reggie Fils-Aimé said himself, that Breath of the Wild's main character Link was hot.