Jokotoba (a preface word) is a rhetoric used mainly in waka (traditional Japanese poems of thirty-one syllables), which is put before a certain word to modify it using a figure of speech, kakekotoba (a rhetoric in Waka in which one word has more than one meaning), and a homophone, etc.
序詞（じょことば）とは、主として和歌に見られる修辞法で、特定の語の前に置いて、比喩や掛詞、同音語などの関係に係る言葉のことである。