本文探討宋代的詩餘說，不僅在於考訂出處，還原詩餘一說的本貌，更重要的是想藉此了解宋代詞體觀念的演進。本文的撰述，先是確認「詩餘」一語出現的時間，以明詩餘觀在宋代衍進的狀況；再藉明清以來詩餘說的幾個中心論點，導入主題，歸納分析宋代詩餘說的內容及意冒；然後論證宋代詩餘觀與東坡「以詩為詞」說的關係。據研究得知，宋人不曾以「詩餘」明指一闋闋的詞，但用「詩餘」作為詞之代稱的看法卻已存在。「詩餘」一語的出現，蓋始於南宋初高宗孝宗間，到理宗時已頗流行，多見於書名、篇名、詩句、文句、詞句及門類別，卻未有明確的定義。今天我們只能從各家言談中歸納其所描述的意涵或陳述的概念去了解「詩餘」的梗概。宋人的詩餘說，普遍是由文體源流的觀點切入看詩詞的關係；亦有由創作主體的內在生命、現實寫作情況論詞之所由生。前者視詞為詩之餘波別派，後者視詞為詩人之餘事、詩文之餘緒。宋人以詞為「詩」之餘，有著詩高於詞的心態在，他們為詞體而辯護，尋源溯流，將詞導入詩的正統，肯定詞體詩化的意義，無非是為了強化詞的功能，提升其文學價值。從創作主體的觀點而視詞為文人創作的餘緒、詩文的餘事者，其實亦隱含兩個意義；一則認定詞體的地位終究不如詩文；一則認為以充裕的德性、有餘的才力為詞，自然能促進詞體質性的改變，不為情欲所役，反而更能尊體，使詞能合於道德的內涵、雅正的風貌以及詩的筆調與意境。宋人的相關論說多有引用、評析或讀賞東坡的字句，由此可見東坡及其詞對宋代詞學的影響，而東坡「以詩為詞」的概念無疑就是了解詩餘觀念如何形成的重要線索。

This paper explores three aspects of the history related to the concept of shiyu which was formed in the Song dynasty. First of all, it examines in detail the period during which the term shiyu was gradually used by critics and writers. The paper also analyses the ways in which the concept appeared. It indicates that the term shiyu first appeared in the early South-ern Song dynasty, most probably in the middle period of the 11th century. However, due to the absence of a clear definition, the meaning of shiyu at that time was quite ambiguous. In the second part, therefore, the paper tries to reconstruct its meaning by examining the various kinds of materials in which the term was found. In brief, shiyu, a term epitomizing what later known as ci, is composed of two characters: shi (poetry) and yu (surplus). The paper indicates that the concept of shiyu as it was formed in the Song dynasty primarily denoted the essence of ci and its origin, while people's sole motive to adopt the term shiyu was to improve the status of ci. Accord-ing to this study, the term "shiyu" probably has two connotations: (1) the source of ci is shi (including various kinds of poetry, such as Shi-jing詩經, yue-fu 樂府 and jin-ti-shi 近體詩 ); and (2) the ci poet uses his/her surplus strength to write ci poetry. Finally, the paper takes into account the far-reaching influence exerted by Su Shi. It argues that Su's famous view on ci, namely " yi-shi wei-ci," had largely shaped other people's tendency to regard ci as shi.