The most widely used term for fitting thought to reality is simply called philosophy. For all of the scraping and arguing over what philosophy is, one theme continually found among philosophers is the notion that their philosophy is the best description of reality. However, we can drill down into something a little more technical and find alternative terminology. For instance, Korzybski referred to the relationship between thought and reality the map-territory relation. You may hear someone accuse someone else of mistaking the map for the territory, which is the charge that one's introspection can be confused by failing to separate one's thoughts from physical reality. From WP:
Mistaking the map for the territory is a logical fallacy that occurs when someone confuses the semantics of a term with what it represents.
We all start with from naive realism when modeling the world, and then use tools like introspection, experiment, and language to model the world. Some, like Searle go on to defend a direct realism and claim belief in representations is a misstep in metaphysics. Most philosophers are comfortable with a representational theory of mind or consciousness (SEP). Such philosophers can be split up broadly among realist and anti-realist camps. I myself have moved from realism to nominalism to conceptualism as I have continued my readings.
After one begins to become familiar with some philosophical ideas, one quickly realizes that the contention among philosophers themselves over what philosophy reveals some interesting intellectual contours about philosophy. These metaphilosophical arguments often boil down to metaphysical differences. In fact, all people in their model of the world are liable to resolve their differences in negotiating reality by, as Quine would put it, semantic ascent. From WP:
[W]hen two people with completely different ideas of whether or not there are such entities as miles, are discussing miles as the objects themselves this discussion will be fruitless. It is in these instances that we see what Quine calls semantic ascent,6: 249–254 the shift from the material mode of language to the formal one. In the formal mode of language we are at a different level. Rather than talking about miles as objects we are talking about what this word 'mile' even means, what it refers to and if it even refers at all. In the formal mode, people with different conceptual schemes might be able to have a reasonable discussion because they are talking about something their conceptual schemes have in common: language.
For your question, it should be noted that there is language that is very much dedicated to the idea that reality and language might have an optimal fit. It's called the correspondence theory of truth. From WP:
In metaphysics and philosophy of language, the correspondence theory of truth states that the truth or falsity of a statement is determined only by how it relates to the world and whether it accurately describes (i.e., corresponds with) that world... Correspondence theories claim that true beliefs and true statements correspond to the actual state of affairs. This type of theory attempts to posit a relationship between thoughts or statements on one hand, and things or facts on the other.
You ask:
Why isn't there a simple logical term for conceptual reality-fitting-success which is closely analogous to "truth" but which is of the logical type that it applies to concepts rather than propositions? Is this just a historical anomaly in the development of logic because Frege enshrined the proposition as the basic unit of logical meaning?
So, I'm going to answer the question coming from Robinson's work Definitions. Whether or not concepts match reality is known as the accuracy of real definition. A real definition, unlike a lexical one which mere describes usage, purports to be language that describes a concept that corresponds to reality. Thus, philosophers in their debate over whether or not concepts are good debate over conceptual definitions. To me personally, this is done best neither by realists nor nominalists, but by conceptualists.
In science, that means that the best models of reality are somewhere between realist and instrumentalist readings. Thus, if a claim about a category of the world, say of types of energy, is in dispute because it is underdetermined by empirical evidence, then the adequacy of theory to carve reality up into categories is a function of pragmatic factors. This implies that theories are not true or false, but are adequate to a degree. Newtonian gravitation, for example, is not true or false, but it is more adequate than Aristotelian physics but inadequate compared to relativistic physics, particularly if one is building a GPS system in space. Adequacy in scientific theory is like satisfiability in mathematics; it's a generalization of the notion of truth.
