The dissertation investigates the semantics and prosody of wh-indefinites, i.e. indefinite expressions that are morphologically related to wh-interrogatives. The first part of the dissertation explores the semantics of wh-indefinites. It identifies a cross-linguistic pattern that bare wh-indefinites (BWIs) appear in more restricted environments than complex wh-indefinites (CWIs), and proposes that the contrasting behaviors of the two types of wh-indefinites are attributed to their different compositional semantics. It also provides a more precise description on the scope configuration of wh-indefinites, refuting the claim in previous works that BWIs cannot take wide scope. The second part of the dissertation concerns the semantics-prosody interface, i.e. how wh-indefinites are distinguished from their interrogative counterparts by prosody. Corpus studies and perception experiments are provided for this purpose, focusing on the case of Korean. The corpus studies indicate that prominence on the wh-word and dephrasing after the wh-word characterize wh-interrogatives, and the experimental results suggest that post-wh dephrasing is the most influential factor in deciding the interpretation of the wh-word. The results further show that the role of phonological prominence on the wh-word is rather to force a wide-scope interpretation, which in turn provides additional empirical evidence for the existence of wide-scope BWIs.