The mainstream study of Chinese compound words adopts the principle of parallelism between morphology and syntax while overlooks, to some degree, the function of semantics in word formation. The purely formal method-based approach, with its own limitations, is unable to offer explanations for the morpheme combination and semantic evolution of compound words. In light of this, it is proposed to adopt an approach in the tradition of Chinese linguistics which makes full use of materials and methods of exegesis and pays more attention to the semantic factors in the study of word formation. The practice of exegesis indicates that core meaning, derived from the original meaning, is a kind of abstract meaning in the deep semantic structure running through and governing the various surface meanings of polysemy. It can also play a unique role in the analysis and explanation of compound words.  Coordinative compounding is one of the most productive methods of generating new words in the Chinese language. Compared with other types of compounding, it is more associated with the semantic relation of monosyllabic words. Hence, coordinative compounding of synonymous morphemes is a ″semantic″ rather than ″grammatical″ mechanism. Previous studies seldom discuss the coordinative compounding at the deep semantic level. As a matter of fact, in many cases, core meanings of monosyllabic words (morphemes) and their relations are the fundamental and deciding factor in the formation of coordinative compound words. From the perspective of core meaning, the deep reason for coordinative compounding and other related word-formation issues can be better explained. As to compound words formed by morphemes with same or similar meaning, the underlying reason for the combination of morphemes lies in the commonality of their core meanings. Cognate words share the same core meaning and the words formed by cognate morphemes, such as ″chun cui (纯粹)″, ″cu shu (粗疏)″ and ″ku he (枯涸)″. They constitute a special type of coordinative compounding. More common are the words formed by non-cognate morphemes with similar core meaning. Three aspects are discussed. Firstly, though the original meanings of component morphemes are different, they have similar semantic features which are the base of word formation, for example ″jin gu (靳固)″. Secondly, it is a prerequisite to distinguish between the original character and phonetic loan character in order to recognize the consistency between core meanings of component morphemes, for example ″rao xi (扰习)″. Thirdly, the commonality of core meanings of component morphemes also lies in the semantic relevance in some aspects, for example ″du mi (笃密)″. As to compound words formed by morphemes with related meanings, the core meanings of morphemes, despite sharing few similarities, are able to determine the relatedness between component morphemes in the surface semantic structure. Three examples are presented. Firstly, the word ″huang huo (惶惑)″ illustrates that the analysis of core meanings helps reveal the correlation between component morphemes in the deep semantic structure and thus provides an explanation for their correlation in the surface structure. Secondly, the word ″jing shuang (竞爽)″ illustrates that the combination of component morphemes is determined by the connection between their core meanings. Thirdly, the word ″qiao qin (翘勤)″ illustrates that the analysis of core meaning is also helpful in revealing the motivation of word-formation of compound words of low-transparency. As to compound words formed by morphemes with opposite meanings, the analysis of core meaning serves to facilitate our understanding of the antonym between component morphemes and the evolution of word meaning. Since the relation between the meaning of a word and its components can be conjunctive, alternative or generative, examples are provided to illustrate different situations: Firstly, in most cases, the core meanings of component morphemes are contradictory to each other and they directly determine the word meaning in the first two kinds of coordinate compound words (conjunctive and alternative), as in the case of ″chong ti (崇替)″. Secondly, in the latter kind of coordinate compound words (generative), word meaning is indirectly determined by the core meanings of component morphemes, as in the case of ″yi wei (依违)″. Thirdly, in certain cases, the core meanings of component morphemes are not directly contradictory to each other. However, they are opposite in certain aspects or dimensions, as in the case of ″you ju (优剧)″. In sum, core meaning is embedded in the deep structure of word meaning. It functions as the more fundamental and decisive factor in the combination of lexical morphemes. The analysis of core meaning contributes to a deepened and expanded synchronic and diachronic study of Chinese polysyllabic words.