I think Enkidoh has captured all of the bullet-points that I would have. To re-state them a bit:

In 1.0, there were lots of references to beast tribes "brainwashing" people to support their cause. This was later proven to be true when the Amalj'aa brought the adventurer and their path companion before Ifrit, who attempted to "temper" them in his flames, only for the attempt to fail and Ifrit release the "Godless Blessed", as the Paragon requested (for some reason). Since then, all references to primal enthrallment have been referred to as tempering.

Indeed, in the Japanese version, tempado is still only major term in use. Enthrallment really is the best term we know, and the game uses it quite often to refer to the tempered. However, be aware that it's an umbrella term used for all sorts of things - tempering, the power dragons have over scalekin, the binding of voidsent (and thus ashkin, considering that - while the game has never stated it outright - I have every belief that ashkin are mortal remains possessed by low-ranking voidsent), etc.

In actuality, while tempering and the effect that the dragons have over scalekin are, I'm sure, different mechanically, the effect is quite similar. A strong, aetherial force completely overwhelms a weaker entity and binds it to the will of the source. In the case of primals, however, this "blessing" can have other effects that warp the receiver with power derivative from their attributes. It changes entities, objects, even the voidsent Nightmare, and this change can rage from increased power (Amalj'aa; Ramuh) to, apparently, warping them into an aurelia-faced monstrosity (Leviathan).