One Name, Many Meanings: How the Library of Congress Navigates Identity, Ambiguity, and Terminological Change

A researcher types a single word into a catalog search field. The system returns results that span geography, biography, political history, and natural science—none of which are what the researcher intended. This is not a software failure. It is, in many cases, a symptom of one of the most persistent structural challenges in library cataloging: the problem of names that mean too many things, or names that once meant one thing and now mean another entirely.

The Library of Congress Subject Headings (LCSH) system is built on the premise that controlled vocabulary can impose order on the enormous diversity of recorded knowledge. But controlled vocabulary depends on words, and words are notoriously unstable. They collide with one another, drift in meaning over time, and carry the ideological weight of the eras in which they were coined. Understanding how LCSH manages these instabilities reveals something important not just about cataloging practice, but about the relationship between language, power, and access.

The Homonym Problem: When One Heading Points in Every Direction

Consider the heading "Washington." Within LCSH, this single string of characters is associated with a former US president, a state in the Pacific Northwest, the nation's capital, a county in dozens of different states, and any number of individuals who share the surname. The system addresses this through what catalogers call disambiguation—the practice of adding qualifiers in parentheses to distinguish between competing meanings.

Thus, "Washington (D.C.)" is differentiated from "Washington (State)," and personal name headings for individuals named Washington are handled within the Name Authority File rather than the subject headings proper. In theory, this is clean and logical. In practice, legacy catalog records, inconsistent application of qualifiers across different cataloging periods, and the sheer volume of records in large library systems mean that disambiguation frequently breaks down at the point of user discovery.

The problem intensifies when dealing with place names that have been applied to multiple geographic locations—a common occurrence in American history, where colonial-era naming conventions frequently duplicated English and European place names across the eastern seaboard. "Springfield," "Franklin," and "Clinton" each refer to multiple distinct municipalities, and LCSH's hierarchical geographic structure must account for all of them without creating false relationships between unrelated entities.

Homophones—terms that sound identical but are spelled differently—introduce a parallel set of complications, particularly in cross-references and catalog displays where auditory similarity can mislead users navigating from one heading to another. While LCSH is primarily a written system, its use in reference interviews and verbal instruction means that phonetic confusion has practical consequences beyond the catalog itself.

Tracking the Drift: How Terminology Shifts Over Decades

Perhaps no dimension of the name problem is more historically significant—or more politically charged—than the revision of terminology used to describe human communities. The evolution of racial and ethnic subject headings in LCSH offers one of the most thoroughly documented examples of how controlled vocabulary both reflects and resists social change.

For much of the twentieth century, LCSH employed the heading "Negroes" as the primary authorized term for African Americans. This usage mirrored the conventions of its era but imposed a vocabulary on library users that grew increasingly at odds with the self-identification of the communities being described. The heading was revised to "Afro-Americans" in 1976, a change that itself reflected the political and cultural currents of the preceding decade. A subsequent revision to "African Americans" came in 1992, aligning the heading with what had by then become the broadly accepted standard in both scholarly and public discourse.

Each of these revisions created a cataloging legacy problem of substantial proportions. Records created under earlier headings were not automatically updated. Libraries with limited retrospective cataloging resources found themselves maintaining collections in which the same body of materials might be discoverable under three different authorized terms, depending on when a given item was cataloged. Cross-references and scope notes help bridge these historical layers, but they do not eliminate the underlying fragmentation.

Similar trajectories can be traced in the headings used to describe Indigenous peoples of the Americas, LGBTQ+ communities, and persons with disabilities—each representing a history of terminology imposed from outside a community, revised under pressure from within it, and leaving behind strata of catalog records that reflect successive moments in that ongoing negotiation.

Authority Control as Infrastructure

The mechanism through which LCSH manages name ambiguity and terminological change is the authority record—a structured document that establishes the authorized form of a heading, records variant forms, and documents the relationships between the authorized heading and related terms. The Library of Congress maintains the Name Authority File and the Subject Authority File as the two primary components of this infrastructure.

For catalogers, consulting the authority record is the standard procedure for resolving uncertainty about a heading's current authorized form. An authority record will typically include a "USE" reference directing catalogers from a deprecated or non-preferred term to the currently authorized form, along with "UF" (Used For) references that identify the variants that have been redirected. Broader and narrower term references situate the heading within LCSH's hierarchical structure.

This infrastructure is functional but imperfect. Authority records are updated as terminology evolves, but the update cycle is not instantaneous. Proposals for new or revised headings must move through a review and approval process, during which the catalog may contain both the deprecated term and early applications of its successor. The gap between the moment when language shifts in scholarly or public usage and the moment when that shift is reflected in an authorized LCSH heading has been a persistent source of criticism—and a recurring subject of professional debate.

The Cataloger's Role in a System Under Tension

Front-line catalogers occupy a distinctive position in this landscape. They are the professionals who must apply the authorized vocabulary to specific items, navigate ambiguities in the record, and make judgment calls when the system's guidance is incomplete or contested. When a heading is under review, when a term is recognized as outdated but not yet officially revised, or when local community usage diverges from the authorized form, catalogers must balance fidelity to the controlled vocabulary against the practical needs of the users they serve.

Some institutions have responded to these tensions by supplementing LCSH with local subject headings or by participating in cooperative efforts—such as the Cataloging Lab's "Toward Reparative Description" project—to propose systematic revisions to problematic terminology. These initiatives reflect a broader recognition that the name problem in LCSH is not merely a technical challenge but a question about whose language the catalog speaks, and whose knowledge it renders visible.

The Library of Congress itself has acknowledged the limitations of its historical vocabulary through formal mechanisms, including the Subject Authority Cooperative Program (SACO), which allows contributing institutions to propose new and revised headings. This distributed model of vocabulary governance is an attempt to make the system more responsive to the full range of communities it serves.

Toward Greater Precision

The name problem in LCSH will not be resolved by any single revision cycle or technological upgrade. It is, at its core, a reflection of the fact that language is a living system, and controlled vocabularies are attempts to hold it still long enough to build something useful. The headings that librarians apply today will carry their own historical signatures into the future, as subsequent generations encounter the choices made in the present.

What the system can do—and what its stewards continue to work toward—is reduce the distance between the vocabulary of the catalog and the vocabulary of the communities who use it. That work requires sustained attention to the name problem in all its forms: the homonyms that scatter search results, the historical terms that linger in legacy records, and the ongoing negotiation over what it means to name something accurately in a world that keeps changing its mind.