Who coined "gamification" term?

Question

According to wikipedia Nick Pelling coined the term "Gamification" in 2002/2003 as part of his bussiness model Conundra.

Though the term "gamification" was coined in 2002 by Nick Pelling,[77] a British-born computer programmer and inventor, it did not gain popularity until 2010.

Reading further gives me some skepticism...

Even prior to the term coming into use, other fields borrowing elements from videogames was common; for example, some work in learning disabilities[80] and scientific visualization adapted elements from videogames.[81]

And above all Yu-kai Chou claims

In short, I’m the creator of the Octalysis Framework (internationally recognized Gamification Framework)

According to a TED video posted in 2014, Yu-kai Chou was researching gamification for about 13 years...that's 2001.

Answer 1

The thesis GAMIFICATION AND THE CREATION OF ACADEMIC WRITER’S IDENTITY says

The history of the term gamification is not necessarily a clear one. According to Burke; Nick Pelling coined the word “gamification” in 2002 for his new consulting business. Pelling defined the word as “applying game-like accelerated user interface design to make electronic transactions both enjoyable and fast” (Burke 5). Pelling’s emphasis was in the hardware though, and the coined term outlasted his failed company (5). In contrast, Deterding et al. say that the first documented use of gamification was in 2008 by the digital media industry, “but the term did not see widespread adoption before the second half of 2010.”

The oldest published use of the term that I can find is in the 2007 book Second Person: Role-playing and Story in Games and Playable Media

I confess that the inspiration for my en-gamification of this ancient and noble pursuit comes from a memorable evening I spent in a coaching-inn outside St Petersburg

but I don't think this is quite the current meaning.

And the 2003 book Dungeons and Dreamers: The Rise of Computer Game Culture : From Geek to Chic:

When the elder student left in 1980, Bartle took it over and "gamified" it. If it were to be a world, it needed inhabitants. If it were to be a game, it needed to be fun.