The word "temporal" is the XXX form of the word "time". What is XXX? I can't find the answer anywhere, I don't even know where to look.
Where to look: temporal in ODO
The word temporal is an adjectival form of the word time.
This is supported by the use of temporal in the entry for time:
In English, any noun can theoretically be made attributive [made into what is effectively an adjective], and that quote could say "which it superseded in time senses," but there is a subtle difference.
One might talk of a time stamp indicating a particular time (for example when a photograph was taken), but to call that a temporal stamp would be unusual. Temporal indicates a relationship to time — it's almost a meta-adjective because it indicates the presence of that relationship.
This relationship is necessary because time (as in "the indefinite continued progress of existence and events in the past, present, and future regarded as a whole"1 rather than a particular point on that continuum) is an abstract noun, so the adjectival form indicates the abstract nature of what it's describing.
1 time, ibid.
Temporal is the adjectival form of time.
is akin to
However, you could also use the adjunct form as the adjective. An adjunct noun adjective is using a noun as an adjective:
Let's analyse the word value thro its various adjectival forms:
Let's analyse time in its various adjectival forms: