First of all, you should read Dr. Ballsun-Staton's definition, from his paper, if you haven't already:
2.3 Nomothetic versus Ideographic
Guba and Lincoln (1994) articulate the nomothetic debate in
social sciences where they note that general theories may not fit
specific cases well: “This problem is sometimes described as the
nomothetic/idiographic disjunction. Generalizations, although
perhaps statistically meaningful, have no applicability in the
individual case.” While their argumentation is in support of
qualitative research, the theoretical basis of the nomothetic as
“law-making” conflict with the ideographic study of the
individual case maps quite strongly onto the axis of form and the
ideas will be used throughout this document. Players seeking the
support of rules are far more nomothetic than those seeking
mimesis with specific, individual cases of reality or imagination.
and (from the Axis of Form section)
Rules, in a role-playing game, represent an encoded mimetic
reflection of the fictional reality of the game filtered through the
author's understanding and stylistic habits. They are an encoded
social contract that players agree to insure that bad or otherwise
undesirable things happen to their characters in ways that appear
realistic or fun. A game where there is no chance of conflict or
failure has no need of rules.
While rules are mimetic themselves, the act of encoding them and
describing the statistical operations upon attempts at agency
changes them from a purely mimetic representation of a world
into a framework for understanding their own reality. Players at a
table then build their own understanding of a world from these
rules, instead of purely trying to mimic reality. However, answers
to rules questions that are not well situated within the rule system
can choose to derive their answer from other rules present in the
system: showing how the edge case is indeed covered by the rules
as written, or may try to describe a mimicable aspect of reality.
The act of using the rules as a reference to uncertain situations
within the rules represents accepting the form of the rules: they
have a structure and a meta-statistical pattern that can be used to
adjudicate the situation in question. The acceptance of the form
of the rules requires that the answers be from or suggested by the
rules and internally consistent with the rules.
On the other side of the axis is the understanding that because the
rules are designed to mimic reality, answers to rules questions
should be drawn from reality as the primary form of the source.
While the rules are a useful mediator, there is no need to draw
upon them to cover edge cases or even to respect their authority
when they imperfectly mimic something from the “real world.”
Most people on the site, however, do not have a pure adherence to
either rules or mimesis but fall between the two extremes. The
articulation of archetypes within this design space is not meant to
indicate that all who belong to a certain archetype always have
answers that are at the extremes of the archetype, but that they are
privileges of mimesis or vice versa.
You should also read the rest of the paper, which is quite good, if a bit sesquipedalian.
The terms are nascent, but are entering the lexicon without too much difficulty.
The terms introduction to English occurred as a result of the work of Wilhelm Windelband, and though their meanings have varied from field to field, Idiographic entities and Nomothetic entities are consistently held to form a dichotomy.
No 'official' noun form of the words currently exist but, like in RPGs, codified rules are typically drawn from some field of expert experience and development occurring outside the codified rules. Basically this means we get to make up our own noun form and see it in a dictionary in a few years if it gets adopted. I suggest Nomothesis and Idiography. In extant philosophical work the adjectival form is frequently just nouned, resulting in phrases like 'the idiographic' and 'the nomothetic'.
In the context of RPGs these mean that the esteemed Dr. Ballsun-Stanton, felt he needed a euphemism for hard-rules systems/players/ideologies/etc (nomothetic gaming social contracts) and soft-rules systems/players/etc (ideographic gaming social contracts). The nomothetic seek and use the general, hence applying the rules to the specific actions of players, while the idiographic seek the specific, hence modifying or ignoring the rules as convenient in achieving mimesis (sameness) with the 'reality' of the game world. Basically a primacy of nomothesis is what drives hard-rules RPGers like myself to seek and uphold 'general' rules (whether they be ones we make ourselves or those in published text) while a primacy of idiography (or, more likely, mimesis itself) is what drives soft-rules RPGers to ignore the rules when they proscribe something contrary to that RPGers conceptualization of the game world.