The occurrence of phrases inside words poses a challenge for theorizing about the boundaries of the domain of word formation as well as the architecture of morphology in general. This entry focuses on phrasal compounds, such as
over‐the‐fence gossip
, as the most typical and productive set of data and examines the structural characteristics and configurational factors playing a role in phrasal compounding. In the first part of this entry, grammatical generalizations in the field of phrasal compounding will be addressed in some detail, laying out the various types of phrasal compounds identified in the literature and highlighting their properties from a typological vantage point. The second part, based on empirical reasoning, investigates configurational and relational aspects and links them to syntactic, semantic and pragmatic traits of phrasal compounds. Lastly, different models of the boundary between the word‐building component of language and syntax are outlined, with examples of how insights from the domain of phrasal compounding are implemented in different accounts. The entry closes with a short conclusion.