The article studies thematic groups of library science and bibliographic terminology that contributes to systematization of the named terminological system. The structure of the analyzed terminological groups, their peculiarities and quantitative characteristics are outlined. There have been collected the terms that differ in their structure: single-word (simple and complex) and consisting of many words (expressed by phrases). For example: indeksuvannia (indexing), ekspres-katalogizatsia (express cataloging), vydavnytcha produktsia (printed output), etc. However, we do not aim to consider the terms of library science and bibliography in this perspective. We would consider these terms by their meaning. Such analysis has enabled us to allocate 10 groups whose meanings are encoded in the core term of the compound structure. These terms include: types of bibliographic manuals and indexes (120 terms), terms to designate editions (113 terms), names of systems and classifications (88 terms), names of types of catalogs and card files (69 terms), terms to designate information (50 terms), titles designating types and kinds of libraries (49 terms), terms for designating types of bibliography (48 terms), names of document types (36 terms), names for the types of library funds (33 terms), titles of library services units (11 terms). Thus, having considered the groups of library science and bibliographic terms in which the primary meaning is encoded in the core term, we have discovered 10 lexical-semantic groups with different numbers of scientific nominations. The largest number of terms (there are 120 units) is used to indicate the types of bibliographic manuals and indexes. The smallest number of terms, there are 11, denote the names of the units of the library services. All this data characterizes the library science and bibliographic terms as a system that has its own distinct structure, hierarchy, and verbal content.